Download IET 7600 Plus Precision LCR Meter Manual

♦ PRECISION INSTRUMENTS FOR TEST AND MEASUREMENT ♦
7600+
Precision LCR Meter
User and Service Manual
IET LABS, INC.
www.ietlabs.com
Email: [email protected]
TEL: (516) 334-5959 • FAX: (516) 334-5988
IET LABS, INC.
www.ietlabs.com
Email: [email protected]
TEL: (516) 334-5959 • FAX: (516) 334-5988
IET LABS, INC.
www.ietlabs.com
Email: [email protected]
TEL: (516) 334-5959 • FAX: (516) 334-5988
IET LABS, INC.
www.ietlabs.com
Email: [email protected]
TEL: (516) 334-5959 • FAX: (516) 334-5988
♦ PRECISION INSTRUMENTS FOR TEST AND MEASUREMENT ♦
7600+
Precision LCR Meter
User and Service Manual
Copyright © 2014 IET Labs, Inc.
Visit www.ietlabs.com for manual revision updates
7600+ im/January 2014
IET LABS, INC.
www.ietlabs.com
Email: [email protected]
TEL: (516) 334-5959 • FAX: (516) 334-5988
♦ PRECISION INSTRUMENTS FOR TEST AND MEASUREMENT ♦
IET LABS, INC.
www.ietlabs.com
Email: [email protected]
TEL: (516) 334-5959 • FAX: (516) 334-5988
WARRANTY
We warrant that this product is free from defects in material and workmanship and, when properly used,
will perform in accordance with applicable IET specifications. If within one year after original shipment,
it is found not to meet this standard, it will be repaired or, at the option of IET, replaced at no charge when
returned to IET. Changes in this product not approved by IET or application of voltages or currents greater
than those allowed by the specifications shall void this warranty. IET shall not be liable for any indirect,
special, or consequential damages, even if notice has been given to the possibility of such damages.
THIS WARRANTY IS IN LIEU OF ALL OTHER WARRANTIES, EXPRESSED OR IMPLIED,
INCLUDING BUT NOT LIMITED TO, ANY IMPLIED WARRANTY OF MERCHANTABILITY OR
FITNESS FOR ANY PARTICULAR PURPOSE.
i
WARNING
OBSERVE ALL SAFETY RULES
WHEN WORKING WITH HIGH VOLTAGES OR LINE VOLTAGES.
Dangerous voltages may be present inside this instrument. Do not open the case
Refer servicing to qualified personnel
HIGH VOLTAGES MAY BE PRESENT AT THE TERMINALS OF THIS INSTRUMENT
WHENEVER HAZARDOUS VOLTAGES (> 45 V) ARE USED, TAKE ALL MEASURES TO
AVOID ACCIDENTAL CONTACT WITH ANY LIVE COMPONENTS.
USE MAXIMUM INSULATION AND MINIMIZE THE USE OF BARE
CONDUCTORS WHEN USING THIS INSTRUMENT.
Use extreme caution when working with bare conductors or bus bars.
WHEN WORKING WITH HIGH VOLTAGES, POST WARNING SIGNS AND
KEEP UNREQUIRED PERSONNEL SAFELY AWAY.
CAUTION
DO NOT APPLY ANY VOLTAGES OR CURRENTS TO THE TERMINALS OF THIS
INSTRUMENT IN EXCESS OF THE MAXIMUM LIMITS INDICATED ON
THE FRONT PANEL OR THE OPERATING GUIDE LABEL.
ii
Contents
1 Introduction ................................................................................................................. 1 1.1 Unpacking and Inspection .................................................................................. 1 1.2 Product Overview ............................................................................................... 1 1.3 Controls and Indicators ....................................................................................... 2 1.4 Accessories Included .......................................................................................... 4 1.5 Accessories/Options Available ........................................................................... 4 1.6 Installation .......................................................................................................... 4 1.6.1 Power Requirements ....................................................................................... 4 1.6.2 Safety Inspection............................................................................................. 5 1.6.3 Safety Symbols ............................................................................................... 8 1.6.4 Disposal .......................................................................................................... 8 2 Operation .................................................................................................................... 9 2.1 Startup ................................................................................................................. 9 2.2 Connection to Device Under Test ....................................................................... 9 2.3 Zeroing .............................................................................................................. 10 2.4 Measurement Procedure ................................................................................... 10 2.4.1 Default Measurement Conditions ................................................................. 11 2.5 Factory default measurement conditions .......................................................... 11 2.6 Menu Functions ................................................................................................ 12 2.6.1 Setup Menu ................................................................................................... 13 2.6.2 Primary Parameter ........................................................................................ 14 2.6.3 Secondary Parameter .................................................................................... 17 2.6.4 Frequency...................................................................................................... 17 2.6.5 AC Test Signal .............................................................................................. 17 2.6.6 DC Bias Voltage ........................................................................................... 20 2.6.7 Range Hold ................................................................................................... 21 2.6.8 Range Locked ............................................................................................... 22 2.6.9 Measurement Delay ...................................................................................... 27 2.6.10 # to Average .............................................................................................. 27 2.6.11 Contact Check ........................................................................................... 27 2.6.12 I/O Menu ................................................................................................... 28 7600 Plus LCR Meter
2.7 151053 A4
Display Type ..................................................................................................... 29 2.7.1 Measured Parameters -.................................................................................. 30 2.7.2 Deviation from Nominal – ............................................................................ 30 2.7.3 % Deviation from Nominal – ........................................................................ 30 2.7.4 Pass/Fail – ..................................................................................................... 31 2.7.5 Bin Summary – ............................................................................................. 31 2.7.6 Bin Number – ................................................................................................ 32 2.7.7 No Display – ................................................................................................. 32 2.7.8 Nominal Value .............................................................................................. 32 2.7.9 Result Format ................................................................................................ 32 2.7.10 Trigger ...................................................................................................... 32 2.7.11 Handler Interface ...................................................................................... 33 2.7.12 RS-232 Interface ....................................................................................... 33 2.7.13 IEEE-488.2 Interface ................................................................................ 34 2.7.14 Print Results .............................................................................................. 34 2.7.15 Results to USB .......................................................................................... 34 2.7.16 Analysis Menu .......................................................................................... 41 2.7.17 Binning...................................................................................................... 43 2.7.18 Absolute Limit .......................................................................................... 44 2.7.19 Tolerance Percent ..................................................................................... 47 2.7.20 Secondary Low ......................................................................................... 47 2.7.21 Secondary High......................................................................................... 47 2.7.22 View Bin Totals ........................................................................................ 48 2.7.23 Zero Bin Totals ......................................................................................... 48 2.7.24 Test Sequencing ........................................................................................ 48 2.8 Parameter Sweep ............................................................................................... 51 2.9 Median .............................................................................................................. 52 2.9.1 Distortion Detection ...................................................................................... 52 2.9.2 Load Correction ............................................................................................ 53 2.9.3 Utilities Menu ............................................................................................... 54 2.9.4 Save Setup..................................................................................................... 55 2.9.5 Recall Setup .................................................................................................. 56 ii
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2.9.6 Setup Accuracy ............................................................................................. 56 2.9.7 Open / Short .................................................................................................. 59 2.9.8 Lock Out ....................................................................................................... 60 2.9.9 Calibration .................................................................................................... 61 2.9.10 Set Time/Date ........................................................................................... 61 2.9.11 Usage/Cal Date ......................................................................................... 62 2.9.12 Set Contrast ............................................................................................... 62 2.9.13 Self Test .................................................................................................... 63 2.9.14 LCD Backlite ............................................................................................ 63 2.10 Input/Output Interface....................................................................................... 63 2.11 Parallel Interface ............................................................................................... 67 2.12 IEEE-488.2 Interface Optional ......................................................................... 68 2.13 Formats ............................................................................................................. 77 2.13.1 Sample Program for National Instruments GPIB card ............................. 78 2.13.2 RS232 Interface ........................................................................................ 79 2.13.3 Results to Printer ....................................................................................... 80 2.14 Operation with Accessories .............................................................................. 80 2.14.1 Rack Mount Kit (7000-00) ....................................................................... 81 2.14.2 BNC Cable Set, 1 Meter (1689-9602), 2 Meter (1689-9602-02) ............. 81 2.14.3 Kelvin Clip Leads (1700-03) .................................................................... 81 2.14.4 Alligator Clip Leads (7000-04)................................................................. 83 2.14.5 Chip Component Tweezers (7000-05) ...................................................... 84 2.14.6 Low V, Axial/Radial Lead Component Test Fixture (7000-06) ............... 85 2.14.7 Open/Short Zeroing: ................................................................................. 86 2.14.8 Low V, Chip Component Test Fixture (7000-07) .................................... 86 2.14.9 Calibration Kit (7000-09) ......................................................................... 88 2.14.10 Connection to "Type 874" Connectors ..................................................... 89 3 Error Messages ......................................................................................................... 90 4 Theory ....................................................................................................................... 93 4.1 Basic Instrument Architecture .......................................................................... 93 4.1.1 Processor Board ............................................................................................ 93 4.1.2 Power Supply ................................................................................................ 93 iii
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4.1.3 LCD Display/Keypad Panel.......................................................................... 93 4.2 7600 Plus Instrument Module ........................................................................... 94 4.2.1 Sine Wave Generator .................................................................................... 94 4.2.2 Voltage Detector Channel ............................................................................. 94 4.2.3 Current Detector Channel ............................................................................. 94 4.2.4 A/D Converter............................................................................................... 94 4.2.5 Digital Signal Processor................................................................................ 94 4.3 Options .............................................................................................................. 94 4.3.1 IEEE-488 Board & Cable ............................................................................. 94 5 Maintenance & Calibration ....................................................................................... 95 5.1 Bias Voltage Fuse Replacement ....................................................................... 95 5.2 Resetting of Time and Date .............................................................................. 95 5.3 Loss of Display Contrast................................................................................... 95 5.4 Calibration ........................................................................................................ 96 5.4.1 Requirements for Re calibration ................................................................... 96 5.4.2 Instrument Return ......................................................................................... 97 Figures
Figure 1 7600 Plus Precision LCR Meter .......................................................................... 1
Figure 2 Front Panel Controls & Indicators........................................................................ 2
Figure 3 Rear Panel Controls & Indicators ......................................................................... 3
Figure 4 Fuse Drawer ......................................................................................................... 5
Figure 5 Test Lead Configuration ....................................................................................... 9
Figure 6 Measured Results Display ................................................................................. 11
Figure 7 Setup Menu......................................................................................................... 13
Figure 8 Primary Parameters ........................................................................................... 14
Figure 9 Series and Parallel Circuits for both Capacitive and Inductive Impedances...... 15
Figure 10 Phase Diagrams of Impedance ......................................................................... 16
Figure 11 Phase Diagrams of Admittance ........................................................................ 16
Figure 12 Secondary Parameter ........................................................................................ 17
Figure 13 AC Test Signal ................................................................................................. 17
Figure 14 Capacitive Reactance vs. Frequency ................................................................ 25
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Figure 15 Inductive Reactance vs. Frequency ................................................................. 26
Figure 16 Measurement Accuracy ................................................................................... 26
Figure 17 I/O Menu ......................................................................................................... 28
Figure 18 Display Type ................................................................................................... 29
Figure 19 Measured Parameters Display .......................................................................... 30
Figure 20 Deviation from Nominal Display ..................................................................... 30
Figure 21 % Deviation from Nominal Display ................................................................ 31
Figure 22 PASS/FAIL....................................................................................................... 31
Figure 23 Bin Summary Display ...................................................................................... 31
Figure 24 Bin Number Display ......................................................................................... 32
Figure 25 RS-232 Setup Format ...................................................................................... 33
Figure 26 IEEE Setup Format ........................................................................................... 34
Figure 27 Analysis Menu .................................................................................................. 42
Figure 28 Binning ............................................................................................................. 43
Figure 29 Absolute Limit .................................................................................................. 45
Figure 30 Absolute Limit (Numeric Entry) ...................................................................... 45
Figure 31 Absolute Limit (Engineering Units) ................................................................ 45
Figure 32 Tolerance Percent ............................................................................................. 47
Figure 33 Bin Totals ........................................................................................................ 48
Figure 34 Sequence Setup (Test Conditions) .................................................................. 48
Figure 35 Sequence Setup (Parameter Selection) ............................................................ 49
Figure 36 Sequence Binning ............................................................................................ 50
Figure 37 Sequence Results ............................................................................................. 50
Figure 38 Parameter Sweep ............................................................................................. 51
Figure 39 Sweep Table ..................................................................................................... 51
Figure 40 Sweep Plot ....................................................................................................... 52
Figure 41 Load Correction ............................................................................................... 53
Figure 42 Utilities Menu .................................................................................................. 54
Figure 43 Save Setup ....................................................................................................... 55
Figure 44 Yes or No......................................................................................................... 55
Figure 45 Recall Setup ..................................................................................................... 56
Figure 46 Setup Accuracy................................................................................................ 57
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Figure 47 Open / Short..................................................................................................... 60
Figure 48 Lockout ............................................................................................................ 60
Figure 49 Set Time / Date ................................................................................................ 61
Figure 50 Usage / Cal Date ............................................................................................... 62
Figure 51 Set Contrast ..................................................................................................... 62
Figure 52 I/O Interface Timing ......................................................................................... 65
Figure 53 I/O Interface Isolation ..................................................................................... 67
Figure 54 RS-232 Cable Configurations .......................................................................... 80
Figure 55 BNC Cable Sets ................................................................................................ 81
Figure 56 Kelvin Clip Leads ............................................................................................ 82
Figure 57 Kelvin Test Leads Open/Short Zeroing........................................................... 83
Figure 58 Alligator Clip Leads ......................................................................................... 83
Figure 59 Chip Component Tweezers ............................................................................. 84
Figure 60 Low V, Axial and Radial Lead Component Test Fixture................................ 85
Figure 61 Low V Chip Component Test Fixture .............................................................. 86
Figure 62 Calibration Kit .................................................................................................. 88
Figure 63 Connection to 874 Connectors ......................................................................... 89
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Specifications
Measurement
Parameters:
Capacitance (Cs/Cp), Inductance (Ls/Lp), Resistance (Rs/Rp),
Dissipation (DF) and Quality (Q) Factors, Impedance (|Z|),
Admittance |Y|, Phase Angle (), Equivalent Series Resistance
(|ESR|), Conductance (Gp), Reactance (Xs), Susceptance (Bp)
Any two parameters measured and displayed simultaneously
Note: s = series, p = parallel, ESR equivalent to Rs
Measurement
|Z|, R, X:
000.0001 m to 99.99999 M
Ranges:
|Y|, G, B:
00000.01 S to 9.999999 MS
C:
00000.01 fF to 9.999999 F
L:
0000.001 nH to 99.99999 H
D:
.0000001 to 99.99999
Q:
.0000001 to 999999.9
Phase Angle: -180.0000 to +179.9999 degrees
Delta %:
Fast
Medium
Slow
LCR:
± 0.5%1
± 0.25%1
± 0.05%1
DF:
± 0.005
± 0.0025
± 0.0005
Measurement
Accuracy:
99.9999 % to +99.9999 %
0.25 x (normal accuracy) with Load Correction implemented and
compared to user supplied standard.
In a range of 3  Z  80k, 100mV  programmed V  1V or
100mV  (programmed I) x (Z)  1V
Test Frequency:
10 Hz to 2 MHz
Resolution: 0.1 Hz from 10 Hz to 10 kHz
5 digits > 10 kHz, 4 digits > 100 kHz
Accuracy: ± (0.01% + 0.10 Hz)
1 At optimum test signal levels, optimum DUT value and without calibration uncertainty error. Instrument accuracy
reduced from nominal specifications when using 7000 accessory fixtures and cables. Best accuracy requires geometric
consistency between that used during open/short zeroing and that used on fixtures and cables during actual
measurement. Consistency may be difficult when using unshielded Kelvin clip and Tweezer type connections.
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Measurement Speed: Fast Accuracy:
Medium Accuracy:
Slow Accuracy:
120 meas/sec
16 meas/sec - 8 meas/sec below 150kHz
2 meas/sec – 1 meas/sec below 150kHz
* may be longer, depending on test conditions & frequency
Ranging:
Automatic, Range Hold, or User-Selectable
Source Impedance:
Trigger:
25, 400, 6.4 k or 100 k, measurement range dependent
Internal (automatic); External (via handler, RS-232 or IEEE 488.2
interfaces)
AC Test Signal
20 mV to 5.0 V (open circuit) in 5 mV steps, <500kHz
Voltage:
20 mV to 1.0 V (open circuit) in 5 mV steps, ≥500kHz to1MHz
20 mV to 0.5 V (open circuit) in 5 mV steps, 1MHz
Accuracy:
± (5% + 1 mV)  100kHz
± (10% + 1 mV) 100kHz to 500kHz
± (20% + 1 mV) 500kHz to 1MHz
± (35% + 1 mV)  1MHz
AC Test Signal
Current:
250 A to 100 mA (short circuit) in 50 A steps
Max Compliance: 3V < 500kHz, 1V from 500kHz - 1MHz; 0.5V > 1MHz
Accuracy:
± (5% +50 A)  100kHz
± (10% +50 A) 100kHz to 500kHz
± (20% +50 A) 500kHz to 1MHz
± (35% +50 A)  1MHz
Bias Voltage:
Internal: 2.0 V External: 0 to ±200 V
Display:
LCD Graphics with adjustable contrast and back light
Results of Dual Measurement Parameters in engineering (7 digits)
or scientific (5 digits) notation
Deviation from Nominal of Primary Parameter
% Deviation from Nominal of Primary Parameter
Instrument Setting and Test Conditions
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Bin Limits and Pass/Fail Results
Plot of Primary Measurement Parameter vs. Test Conditions
Table of Measurement Parameters vs. Test Conditions
Sequenced Test Results Summary
Limit Detection:
Interfaces:
15 bins total (10 pass, 4 fail, 1 no contact)
Standard: RS-232, Handler, Printer Port, USB; Optional:
IEEE488.2
Front Panel
Four terminal (BNC)
Environmental:
MIL-T-28800E, Type 3, Class 5, Style E & F.
Operating: 0o to + 50o C. Storage: - 10o to + 60o C.
Humidity:
< 75% for 11o C to 30 o C operating
Altitude: <2000m, Installation Category 1, Pollution Degree 1
Mechanical:
Bench mount with tilt bail
Dimensions: (w x h x d): 410 x 150 x 360mm
Weight:
Power Requirements: 90 to 250Vac
Other Features:
8kg net, 10.5kg shipping
47 - 63 Hz
100W maximum
Charged Capacitor Protection: 8 / C for Vmax  250 V
2 / C for Vmax  1000V
C = Capacitance in farads of the device under test
Measurement Delay programmable from 0-1000 ms in 1 ms steps
Measurement Averaging programmable from 1-1000
Median value Mode
Open and Short Circuit Zeroing at Multiple Frequencies
Power Fail Protection (setting, results, & calibration data stored)
Storage and Recall – Internal Memory, USB, ASCII format
Self-Test Routines at Power-up
Self Accuracy Calibration and Display
Contact Check
Supplied:
151053 Instruction Manual, Power Cable, Calibration Certificate
and Flash-118 USB Memory Stick
Ordering Information Catalog No.:
ix
7600 Plus LCR Meter
7600 Plus Precision LCR Meter
151053 A4
7600
Options & Accessories:
x
Rack Mount Kit
7000-00
BNC Cable Set, 1 meter
1689-9602
BNC Cable Set, 2 meters
1689-9602-2
Kelvin Clip Leads
1700-03
Alligator Clip Leads
7000-04
Chip Component Tweezers
7000-05
Low Voltage Axial/Radial Lead Component Test Fixture
7000-06
Low Voltage Chip Component Test Fixture
7000-07
Calibration Kit
7000-09
RS232 Cable
630158
USB to RS232 Adapter
630250
7600 Plus LCR Meter
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151053 A4
Introduction
1.1
Unpacking and Inspection
Inspect the shipping carton before opening; if damaged, contact the carrier’s agent
immediately. Inspect the instrument for any damage. If the instrument appears damaged
or fails to meet specifications, notify IET Labs or its local representative. Retain the
shipping carton and packing material for future use such as returning for re calibration or
service.
1.2
Product Overview
The 7600 Plus Precision LCR Meter is an automatic, user-programmable instrument for
measuring a wide variety of impedance parameters. The 7600 Plus covers a frequency
range from 10 Hz to 2 MHz with a basic measurement accuracy of 0.05%. The
instruments high resolution graphics display and keypad makes for easy menu
programming. Test conditions are stored and recalled from internal memory, eliminating
wasted measurement setup time.
Extensive pass/fail binning capability and
measurements speeds of up to 120/sec makes the unit well suited for production
applications.
The instruments unique measurement sequencing allows up to six parameters to be
measured on a single pass. Additionally, a parameter can be plotted against a test
condition variable, an invaluable technique for component design and product evaluation.
The 7600 Plus comes with RS-232, I/O port (handler), USB host port, and parallel
interfaces, all standard, for remote control operation and communication with other
instrumentation. The USB host port is included for program/data storage of test
conditions and measurement results, and for transferring these files to a PC. The 7600
Plus can be used with most USB memory sticks that are FAT16/FAT32 format;
maximum consumption current must be below 500 mA. The memory stick can be
installed and removed at anytime. The USB stick is automatically mounted when
installed. The USB host port complies with USB v2.0 standard. The USB host port is
not designed to be connected to a PC, Printer or USB hub.
Figure 1 7600 Plus Precision LCR Meter
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1.3
151053 A4
Controls and Indicators
Figure 2 shows the controls and indicators on the front panel of the 7600 Plus.
Figure 2 Front Panel Controls & Indicators
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Figure 3 shows the controls and indicators on the rear panel of the 7600 Plus.
Figure 3 Rear Panel Controls & Indicators
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1.4
151053 A4
Accessories Included
151053 Instruction Manual
1
Calibration Certificate
1
Power Cord (CE units with international cord set)
1
Fuse (T2.5A, 250V, 5x20mm, for 115/220V operation)
1
FLASH-118 512Mbyte Memory Stick
1
1.5
Accessories/Options Available
Rack Mount Kit
7000-00
BNC Cable Set, 1 meter
1689-9602
BNC Cable Set, 2 meters
1689-9602-02
Kelvin Clip Leads
1700-03
Alligator Clip Leads
7000-04
Clip Component Tweezers
7000-05
Low Voltage Axial/Radial Lead Component Test Fixture
7000-06
Low Voltage Chip Component Test Fixture
7000-07
Calibration Kit
7000-09
RS232 Cable
630158
USB to RS232 Adapter
630250
1.6
Installation
The 7600 Plus contains a high resolution back lit LCD for convenient viewing. The
optimum angle for viewing is straight onto the display. This means that for bench
operation the front bail should sometimes be used to angle the instrument up and for rack
installation it should be mounted somewhat at eye level.
1.6.1
Power Requirements
The 7600 Plus Precision LCR Meter can be operated from a power source between 90
and 250Vac at a power line frequency of 47 to 63Hz, no line voltage switching is
necessary. Power connection to the rear panel is through an ac inlet module comprised of
an ac connector and fuse drawer. Always use an outlet that has a properly connected
protection ground. Before connecting the 3-wire power cord between the unit and AC
power, verify the fuse is in accordance with the power source, T2.5A, 250V, 5x20mm
(IET Labs PN 520049) for 115 or 220V source. The 7600 Plus is factory shipped with
the 2.5A fuse in place. The instrument can be damaged if the wrong fuse is installed. To
change the fuse, proceed as follows: Procedure
1. Make sure the unit has been disconnected from its ac power source for at least
five minutes before proceeding.
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2. Remove the fuse drawer by inserting a small flat head screwdriver behind the
small tab to force the draw outward. Refer to Figure 4.
3. Once the fuse drawer has been completely removed from the instrument remove
the clear fuse tray from the drawer by lifting upward slightly on the long narrow
black locking tab. This will allow the fuse tray to be removed from the fuse
drawer. This tray contains the active fuse, left side (secured by holder) and spare
fuse on the right side (if present).
4. Remove the active fuse from the holder by prying upward using a small flat head
screwdriver. Insert the replacement fuse into the fuse holder.
5. Once the fuse has been installed in the holder and spare fuse (if desired) installed
in the right side of the tray insert the tray back into the fuse drawer, push in and
lock. The two silver contacts on the fuse tray should be positioned towards the
outside.
6. Once the fuse tray has been installed in the draw, reinstall the fuse drawer back
into the instrument ac inlet module, push in and lock.
Act ive fuse in holder
t his side
Cont act s
Locking
t ab
Spar e
fuse
t his
side
Figure 4 Fuse Drawer
1.6.2
Safety Inspection
WARNING
If this instrument is used in a manner not specified in this manual, the operator and
the equipment are at risk.
1. Never touch the metal of the High Voltage probe directly.
insulated parts of the lead(s).
Touch only the
2. Never touch the test leads, test fixture or DUT in any manner (this includes
insulation on all wires and clips) when the high voltage is applied and the red
DANGER light is ON.
3. Before turning on the Guardian unit, make sure there is no device (DUT) or
fixture connected to the test leads.
4. After each test, press the [STOP] (red) button for safety. This terminates the high
voltage being applied to the output terminals.
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5. When the red DANGER LED is lit or flashing, NEVER touch the device under
test, the lead wires or the output terminals.
6. Before touching the test lead wires or output terminals make sure :
a) The red [STOP] button has been pressed
b) The red DANGER LED is OFF.
7. In the case of an emergency, turn OFF the POWER switch using a “hot stick” and
disconnect the AC power cord from the wall.
DO NOT TOUCH THE
INSTRUMENT.
8. Position the equipment so it is easy to disconnect. Disconnect by means of the
power plug or power connector.
9. If the DANGER LED does not go off when the [STOP] button is pressed,
immediately stop using the tester. It is possible that the output voltage is still
being delivered regardless of the TEST ON/OFF control signal.
10. When the instrument is remotely controlled, be extremely careful. The High
Voltage Output is being turned On/Off with an external signal.
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CAUTION
Before operating the instrument, inspect the power inlet
module on the rear of the 7600 Plus to ensure that the
properly rated fuse is in place, otherwise damage to unit
is possible.
When the 7600 Plus is installed in a rack (using the IET
Labs 7000-00 Rack Mount Kit) verify the unit is secured
using the cabinet mounting rails and not solely by the
front panel angle brackets.
In bench or rack mount applications, the instrument should
be positioned with consideration for ample airflow. Verify
an open space of at least 3 inches (75mm) behind the rear
panel. The surrounding environment should be free from
excessive dust to prevent contamination of electronic
circuits.
The 7600 Plus is shipped with a standard U.S. power cord,
IET Labs PN 4200-0300 (with Belden SPH-386 socket or
equivalent, and 3 wire plug conforming to IEC 320) or with
an approved international cord set. Make sure the
instrument is only used with these cables (or other
approved international cord set) that ensures the instrument
is provided with connection to protective earth ground.
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1.6.3
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Safety Symbols
The product is marked with the following safety symbols.
!
Product will be marked with this symbol (ISO#3864) when it is necessary for the user to
refer to the instruction manual in order to prevent injury or equipment damage.
Product marked with this symbol (IEC417) indicates presence of direct current.
Product will be marked with this symbol (ISO#3864) when voltages in excess of
1000V are present.
Indicates the grounding protect terminal, which is used to prevent electric shock
from the leakage on chassis. The ground terminal must connect to earth before
using the product.
Procedure can cause hazard to human if the warning is neglected.
Warning
Caution
Avoid product misuse. It may cause damage to the product itself and the DUT if
the caution is neglected.
Important information or tips for the procedures and applications.
Note
Warning Signal During Testing
“DANGER – HIGH VOLTAGE TEST IN PROGRESS, UNAUTHORIZED PERSONS
KEEP AWAY”
1.6.4
Disposal
Do not dispose of electrical appliances as unsorted municipal
waste, use separate collection facilities. Contact your local
government for information regarding the collection systems
available. If electrical appliances are disposed of in landfills or
dumps, hazardous substances can leak into the groundwater and
get into the food chain, damaging your health and well-being.
When replacing old appliances with new one, the retailer is
legally obligated to take back your old appliances for disposal.
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Operation
Once the 7600 Plus is powered up it is ready immediately for testing, at default test
conditions, by pressing the START button. Any of these conditions and all other
instrument operations can be changed by easy-to-use menu functions, for simplicity of
understanding, descriptions and uses of all these functions refer to menu discussions
starting on page 12. The Contents list in the front of this manual should be used for
quickly locating specify subjects of interest.
2.1
Startup
Connect the instrument power cord to the source of proper voltage. The instrument is
to be used only with three-wire grounded outlets.
Power is applied to the 7600 Plus by pressing the POWER button on the front panel.
The instrument runs a self test and any error messages are displayed accordingly.
2.2
Connection to Device Under Test
The 7600 Plus unit employs a four terminal measurement configuration that permits easy,
accurate and stable measurements and avoids mutual inductance, interference from
measurement signals, noise and other factors inherent with other types of connections.
To maintain measurement integrity IET Labs makes available a number of accessory
cable sets and fixtures for connection directly to the front panel BNC connectors. Refer
to section 1.5 on page 4 for a list of available accessories.
Figure 5 Test Lead Configuration
Figure 5 shows the 7600 Plus connector configuration and a typical four terminal
connection to the device under test. H and L on the 7600 Plus denote polarity of AC
test signal at the measurement terminals as well as + and - polarity of DC bias
voltage when applied to the DUT.
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WARNING
When DC bias is applied, the PH connection carries a positive DC voltage with
respect to ground.
2.3
Zeroing
Before making measurements, the 7600 Plus should be zeroed to correct for test lead
and/or fixture errors. During the zeroing process corrections are calculated and stored in
instrument memory and applied to ongoing measurements. Measurement accuracy is
specified at the end of the IET Labs one meter cable (7000-01). Perform the Open and
Short circuit zeroing with the cables and fixtures to be used during testing. In order to
maintain instrument accuracy with other cable lengths the instrument should be re
calibrated using the IET Labs 7000-09 Calibration Kit and the alternate cable. Generally
the unit should be zeroed at least once per day and each time test leads or fixture is
changed. It is not necessary to re-zero if the test frequency is changed. The zeroing
routine is accessed through the Utilities Menu as follows:
1. Press MENU key
2. Press LEFT/RIGHT ARROW to select Utilities menu
3. Press UP/DOWN ARROW key for Open / Short
4. Press ENTER
Follow the instructions shown on the LCD display for open and short circuit zeroing of
test leads and/or fixture. During the Open Test the leads or fixture should be open with
no component connected. During the Short Test leads should be connected or fixture
shorted (using a clean copper wire, as short as possible). When zeroing, Contact Check
should be OFF, # to Average to 1 and Median OFF.
2.4
Measurement Procedure
Whenever the 7600 Plus is powered up it is ready immediately to begin measuring
at default test conditions. Initially, these conditions will be set to factory default but
can be changed by the user and stored to overwrite factory default. To initiate a test
once a device is connected press START, the LCD display shows the measured results
and test conditions similar to the illustration of Figure 6.
NOTE:
For optimum measurements, warm up for 30 minutes.
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Measured Parameters
RETST
Voltage
Cs
DF
17.52510 pF
0 .0000500
1.0000kHz
Auto
0 ms
Freq
Range
Delay
AC Signal
Average
Bias
1.000V
1
Off
Figure 6 Measured Results Display
2.4.1
Default Measurement Conditions
A set of default measurement conditions are initially established at the factory and stored
in instrument memory. Default conditions are those that determine the instruments status
on power up, thus the instrument is always set to a known state before any testing begins.
These conditions can be changed by the user for tailoring to a specific application. Refer
to section 2.9.4 on page 55.
2.5
Factory default measurement conditions
Under Setup Menu
Primary Parameter - Auto
Secondary Parameter - None
Frequency - 1 kHz
AC Test Signal - 1V
DC Bias Voltage - Off
Range Hold - Off
Range Locked - 0
Measurement Accuracy - Medium
Delay Time - 0
# to Average - 1
Contact Check - Off
Under I/O Menu
Display Type - Measured Parameters
Nominal Value - None
Result Format - Scientific
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Trigger - External
Handler - Off
RS-232 - Enabled
IEEE - Disable
Print Results – Off
Results to USB - Off
Under Analysis Menu
Binning - None
Test Sequencing - Off
Parameter Sweep - Off
Median - Off
Distort Detect - Off
Load Correction - Off
Under Utilities Menu
Lockout - Off
Backlite - On
2.6
Menu Functions
All programmable functions of the 7600 Plus are controlled by easy to use menu
displays. The user enters the menu mode by selecting the MENU key which calls up four
top level menus, Setup, I/O, Analysis and Utilities. Each one of these is comprised of a
sub menu list whose functions are described in detail below. Finding ones way around
the menu listing is accomplished using the UP, DOWN, RIGHT and LEFT arrow keys
as indicated on the adjacent LCD display. A highlighted menu function can be
controlled by selecting the ENTER key, making the desired entry or selection and
pressing ENTER again to implement.
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2.6.1
151053 A4
Setup Menu
Setup
I/0
Analysis
Primary Parameter
Secondary Parameter
Frequency
AC Test Signal
DC Bias Voltage
Range Hold
Range Locked
Measurement Accuracy
Measurement Delay (ms)
# to Average
Contact Check
Utilities
>>
>>
= 1.0000 kHz
Off
Off
=0
Int
On
>>
Ext
>>
=0
=1
Off
On
Figure 7 Setup Menu
The first of the four main menus is Setup, shown above. Each function controls a 7600
Plus measurement condition and is described in detail below.
Setup
I/O
Analysis
Utilities
Primary Parameter
Secondary Parameter
Frequency - (numeric entry)
AC Test Signal - Voltage
- Current
- Value - (numeric entry)
DC Bias Voltage - Off
- Int
- Ext
Range Hold - Off
- On
Range Locked - (numeric entry)
Measurement Accuracy
- Fast
- Medium
- Slow
Measurement Delay - (numeric entry)
# to Average - (numeric entry)
None
DF
Q
|ESR|

Rs
Rp
Gp
Cs
Cp
Ls
Lp
|Z|
|Y|
Xs
Bp
Auto
Cs
Cp
Ls
Lp
Rs
Rp
DF
Q
|Z|
|Y|

|ESR|
Gp
Xs
Bp
Contact Check - Off
- On
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2.6.2 Primary Parameter
Analysis
Setup
I/0
Utilities
Pri Param
Auto
Cs
Cp
Ls
Lp
Rs
Rp
DF
Q
|Z|
|Y|
(more)
HIT MENU TO RETURN TO MAIN MENU
Figure 8 Primary Parameters
Additional Parameters not shown and selected by UP/DOWN arrow keys include: ,
|ESR|, Gp, Xs, Bp
Any combination of two parameters can be measured and displayed simultaneously on
the 7600 Plus, one referred to as the Primary (displayed first) and the other the
Secondary. The instrument as powered up provides a default primary parameter
selection of Auto, a feature which enables any passive component to be measured
without knowing what type of component it is. Depending on the component type the
primary and secondary default could be Cs & DF, Rs & Q, or Ls & Q. The parameter
selection can be chosen by the operator through menu selection. Besides Auto, the
following selections are possible and discussed in more detail below.
Cs - Capacitance in farads
|Z| - Impedance in ohms
Cp - Capacitance in farads
|Y| - Admittance in siemens
Ls - Inductance in henries
 - Angle in degrees
Lp - Inductance in henries
|ESR|-Equivalent series resistance in ohms
Rs - Resistance in ohms
Gp - Conductance in siemens
Rp - Resistance in ohms
Xs - Reactance in ohms
DF- Dissipation Factor (no units)
Bp - Susceptance in siemens
Q - Quality Factor (no units)
s = series equivalent circuit
p = parallel equivalent circuit
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An impedance that is neither a pure resistance nor a pure reactance can be represented at
any specific frequency by either a series or a parallel combination of resistance and
reactance. Such a representation is called an equivalent circuit. The value of the primary
measurement of a device depends on which equivalent circuit, series or parallel, is
chosen to represent it. The manufacturer or user of a device specifies how a device is to
be measured (usually series) and at what frequency. If this is not known, be sure to
specify if the results were series or parallel and what the measurement frequency was.
Series and parallel equivalent circuits for a lossy inductor and lossy capacitor are shown
in Figure 9.
Rs
Rs
Cp
Cs
Rp or
Gp
Rp or
Gp
Lp
Ls
Figure 9 Series and Parallel Circuits for both Capacitive and Inductive Impedances
Impedance is the parameter used to characterize electronic sensors, components,
materials and circuits. Impedance |Z| is defined as the opposition a device or circuit
offers to the flow of ac current at a particular frequency and generally represented as a
complex quantity consisting of a real part (resistance, R) and imaginary part (reactance,
jX). Impedance can be expressed using the rectangular coordinate form (R + jX) or polar
form as magnitude and phase angle (|Z| ). Figure 10 shows the mathematical
relationship between R, X, |Z|, and  for both inductive and capacitive devices. In some
cases it becomes mathematically practical to represent impedance using the reciprocal
where 1/|Z| = |Y| = G + jB, where |Y| represents admittance, G conductance, and B
susceptance. This mathematical relationship is shown in Figure 11 for inductive and
capacitive devices.
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151053 A4
+jX
Rs


Z
+j Ls
+R

-j/ Cs

Z
Impedance
-jX
+R
Rs
-jX
Capacitance
Inductance
Figure 10 Phase Diagrams of Impedance
Capacitance
Inductance
+jB
+jB
Gp
Y
j Cp



Gp
-jB
+G

+G
Admittance
-j/ Lp
Y
-jB
Figure 11 Phase Diagrams of Admittance
Quality factor (Q) is used as a measure of a reactance's purity (how close it is to being a
pure reactance, i.e. no resistance) and defined as the ratio of the energy stored in a device
to the energy dissipated by the device. Q is dimensionless and is expressed as Q = X/R =
B/G. One can see that Q is the tangent of the angle . Q is commonly applied to
inductors and for capacitors the term generally used to express purity is Dissipation
Factor (D), which is the reciprocal of Q.
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Any parameter, primary or secondary, can be chosen as the default parameter at power
up.
2.6.3 Secondary Parameter
Setup
I/0
Analysis
Utilities
Sec Param
None
DF
Q
ESR

Rs
Rp
Gp
Cs
Cp
Ls
(more)
HIT MENU TO RETURN TO MAIN MENU
Figure 12 Secondary Parameter
Additional Parameters not shown and selected by UP/DOWN arrow keys include: Lp,
|Z|, |Y|, Xs, Bp
As in the primary parameter selection, any one parameter can be chosen by the operator
for display. The instrument as powered up provides a default secondary parameter.
When the default primary parameter is Auto the secondary parameter is dependent and
determined by it. If the primary default is Cs the secondary defaults to D. If the primary
default is Ls or Rs the secondary defaults to Q. The parameter selection can be chosen by
the operator through menu selection.
2.6.4 Frequency
Numerical entry accepts up to five digits with decimal, of the desired test frequency
between 10 Hz and 2 MHz. Resolution of setting is 0.1 Hz from 10 Hz to 10 kHz, 5
digits above 10 kHz.
Units of frequency, Hz, kHz, or MHz are selected by the UP/DOWN arrow keys.
2.6.5 AC Test Signal
Setup
I/0
AC Signal
Signal Type
Signal Value
Analysis
Voltage
= 1.000 V
Utilities
Current
HIT MENU TO RETURN TO MAIN MENU
Figure 13 AC Test Signal
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Allows selection of the AC Signal Type as a Voltage source or Current source,
RIGHT/LEFT arrow keys.
With Signal Type selected as Voltage, Signal Value accepts entry of a value between
0.020 and 5 volts* (open circuit) in 0.005 V steps.
With Signal Type selected as Current, Signal Value accepts entry of a value between
0.00025 and .1 amp (short circuit) in 0.00005 amp steps.
Numerical values can be entered directly with units. Units for voltage value, mV or V
and units of current value, A, mA, or A are selected by the UP/DOWN arrow keys.
Any numerical entries with resolution greater than 0.005V (5 mV) for voltage or
0.00005A (50 A) for current will be truncated or ignored.
In voltage mode the selected voltage is maintained at the instrument test terminals with
the terminals open, but not necessarily at the device under test. In current mode the
selected current is maintained at the device under test, independent of changes in the
device's impedance. It should be noted that even though the maximum programmable
current is 100 mA the instrument is limited to a compliance voltage of 3 volts* in
current mode, i.e. (I) times (Z) must be less than 3 volts otherwise erratic measurement
results could occur.
The current required to test a device may exceed 100 mA if the source voltage is
programmed to greater than 2.5 V. To determine the current required use the following
formula:
I  V prog  (25  Rdut ) 2  ( X dut ) 2
If the current is greater than 100 mA, reduce the program voltage, otherwise
unpredictable measurement results may occur.
* 1 volt above 500 kHz, 0.5 volts above 1 MHz
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Maximum Reccomended Test Frequency in Current Mode
vs.
Inductance
1.0E+6
400 kHz
100.0E+3
Testing in current mode
may give Q errors for
inductors above this line
Current Testing OK
below this line
10.0E+3
35 kHz
_________
sqrt(L(mH))
1.0E+3
1.00E-06
1.00E-05
1.00E-04
1.00E-03
1.00E-02
1.00E-01
1.00E+00
Maximum Test Frequency vs. Measured Inductance (In Current Mode)
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2.6.6 DC Bias Voltage
Allows selection of a dc Bias Voltage of Off, Internal or External.

Off - When selected no dc bias voltage is applied to the device under test.

Int - When selected an internal bias voltage of 2 volts is applied to the device under
test. Internal bias can not be programmed if the AC Test Signal is programmed for >
4V at 500kHz.

Ext - When selected an external bias voltage between 0 and ±200 volts can be
applied to the device under test by way of the rear panel external bias connection.
CAUTION
Make sure the AC test Signal is selected for VOLTAGE and not Current before
switching to INT (internal) or EXT (external) bias. This also applies to the instrument's
Default setup at power-up or any setups recalled from memory, they MUST be set to
VOLTAGE before applying bias. If programmed to CURRENT the instrument can
sustain damage from any external source or from a charge stored on the device under test
WARNING
When using external bias, unit must be programmed for EXT bias before the
external bias supply is connected to the 7600 Plus.
External bias supply must be returned to zero volts and turned off before switching
back to the OFF or INT mode.
The BIAS ON indicator, adjacent to the BNC measurement terminals, serves to indicate
if external bias has been called for. It indicates that external bias connections have been
switched in, but not necessarily the presence of external bias.
When dc bias is to be applied to a device observe the correct polarity when connecting
the bridge or inserting the device in a test fixture. Bias POSITIVE polarity is applied
to the high terminals (PH, IH), and bias NEGATIVE polarity applied to the low
terminals (PL, IL). It is good practice to wait approximately 1 second after initiating a
measurement before taking a reading, this allows the device to stabilize after bias is
applied. When the instrument is triggered remotely, a programmed delay is advisable to
ensure that the device has stabilized.
If bias is required at voltages other than the internal 2 volts, an external bias can be used
as discussed below.

Be sure that the voltage does not exceed ±200 volts.

A current limiting voltage supply is recommended, with a limit set at 200 mA.

The bias supply must be floating, DO NOT connect either side to ground. When
using a single polarity supply for positive or negative biasing, observe proper polarity
when connecting to the 7600 Plus. For positive bias the positive output of the supply
must be connected to Bias Voltage + and the negative to Bias Voltage -. The
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151053 A4
opposite is true for negative bias, the negative output of the supply must be connected
to the Bias Voltage + and the positive to Bias Voltage -.

Generally the external circuit must provide switching for both application of bias
after the device is connected and discharge before it is removed.

A well-filtered supply is recommended. Hum can affect some measurements,
particularly at power line frequencies.When applying a bias voltage there are effects
to be aware of in watching for stabilization of the DUT: voltage and capacitance.
Besides charging to a final voltage, there is also the stabilization of capacitance value
itself. For example, some electrolytic capacitors respond slowly to a change in
applied voltage, therefore the capacitance can be changing well after the voltage is
stable. In general DC bias should only be applied to capacitors, unreliable
measurement results can occur if DC bias is applied to low impedance devices.
When applying external bias on capacitors below 200pF with an AC signal level
below 100mV the instrument can exhibit excessive noise.
2.6.7 Range Hold
Allows selection of Range Hold Off or On. To eliminate operator errors in range
setting and ensure specified instrument accuracy the 7600 Plus Range Hold should
generally be left Off. There may be exceptions to this when repetitive measurements are
to be made over a concentrated range of values and there is a desire to reduce test time by
eliminating range switching.

Off - When selected the instrument automatically selects the optimum range for the
test voltage and test frequency selected and the impedance being measured.

On - When selected the range is held based on the one currently selected, 1 through
59 in voltage mode or 33 through 159 in current mode. The one currently selected is
best determined by measuring the device with Range Hold to Off. Measured results
outside the bounds of a selected range will be indicated by an OVER RANGE or
UNDER RANGE display message.
NOTE:
The 7600 Plus unit provides an extensive array of range switching based on the user test
conditions selected and impedance being measured.
One of the most important uses of the range holding capability is to avoid range changes
when the component is removed from a fixture when repetitive internal triggering is
selected. With no component connected the instrument can go into a range search and
time is lost when the next component is connected. Another use of range hold occurs
when measuring components of the same nominal value whose actual values spread
across the boundary of two ranges. If allowed to auto range, the units and decimal point
can change with the range and confuse the operator. It is important to note that when a
range is held which is not the range the instrument auto ranging would have
selected, some accuracy may be sacrificed.
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Under certain circumstances high Q inductors can cause extraneous overload conditions
if they are tested at frequencies where the inductor resonates with the test leads. This
situation can be avoided by one or more of the following: test at a voltage substantially
below full scale voltage for a given range; use low capacitance cables; or test at a
frequency below the resonant frequency of the inductor with the test leads.
2.6.8 Range Locked
Accepts entry of selected measurement ranges between 0 and 59 (as listed below), 0 for
no range locked and others for the selected range. Measurement ranges are a function of
the impedance being measured (Z), selected test frequency (F) and ac test voltage (V).
For best measurement results the instrument is generally recommended to operate with
Range Hold to Off and Range Locked to 0. It is possible to calculate a range, based on
Z, F and V, as detailed below.
AC Signal Voltage Mode
Measurement Range #'s
1
17
33
49
2
18
34
50
3
19
35
51
5
21
37
53
6
22
38
54
7
23
39
55
9
25
41
57
10
26
42
58
11
27
43
59
Determine Range where R# = R1 + R2 + R3
where R1
= 1 and K* = 10 A if F < 25 kHz and I < 10 A
= 17 and K* = 160 A if F < 200 kHz and I < 160 A
= 33 and K* = 2.56 mA if I < 2.56 mA
= 49 and K* = 40 mA if I  2.56 mA
* value for K required in calculation of R3 below
I
Vi
Vi
Z  25
= 10V if V  0.1V
= V if V > 0.1 and < 1.01
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151053 A4
= V/5 if  1.01
V = programmed ac test voltage
Z
= impedance value Z in ohms of the device
under test.
where R2
= 0 if (I)(Z) > 0.25
= 1 if (I)(Z) > 0.1
= 2 if (I)(Z) > 0.025
where R3
= 0 if I / K > 0.25
= 4 if I / K > 0.1
= 8 if I / K > 0.025
Note: above 1.5 MHz R2 and R3 are always 0 (zero)
AC Signal Current Mode
Measurement Range #'s
33
49
133
149
34
50
134
150
35
51
135
151
37
53
137
153
38
54
138
154
39
55
139
155
41
57
141
157
42
58
142
158
43
59
143
159
Determine Range where R# = R + R1 + R2 + R3
where R
= 33 and Rs = 400 if I  2.2mA
= 49 and Rs = 25 if I  2.2mA
I = programmed ac test current
where R1
= 0 and Vs = 1.0 if EDUT or EDET  1.0
= 100 and Vs = 5.0 if EDUT or EDET  1.0
EDUT = (I) (Z) this value must be less than 3.0, reference paragraph
2.6.2.4 AC Test Signal
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EDET = (I) (Rs)
Z
= impedance value Z in ohms of the device
under test (refer to Figures 2-11 and 2-12
to help determine Z in terms of capacitive
and inductive reactance).
where R2
= 0 if EDUT/Vs  0.25
= 1 if EDUT/Vs  0.25
= 2 if EDUT/Vs  0.1
where R3
= 0 if EDET/Vs  0.25
= 4 if EDET/Vs  0.25
= 8 if EDET/Vs  0.1
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Capacitive R eactance (Xc=1/(2pifC))
1000000000
100000000
10000000
1000000
0.1pF
Ohms
100000
1.0pF
10000
10pF
1000
100pF
100
1.0nF
10
10nF
1
100nF
0.1
10mF
0.01
10
100
1000
1.0mF
10000
100uF
100000
10uF
1000000
1.0uF
10000000
Freque ncy
Figure 14 Capacitive Reactance vs. Frequency
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151053 A4
Inductive Reactance (Xl=2pifL)
1000000000
1kH
100H
100000000
1H
10000000
100mH
1000000
10mH
100000
Ohms
10H
1mH
10000
100uH
1000
10uH
100
1uH
10
100nH
1
10nH
0.1
0.01
10
100
1000
10000
100000
Frequency
Figure 15 Inductive Reactance vs. Frequency
Setup
I/0
Accuracy
Fast
Medium
Slow
Analysis
Utilities
.5%
Voltage
.25%
.05%
HIT MENU TO RETURN TO MAIN MENU
Figure 16 Measurement Accuracy
26
1000000
10000000
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151053 A4
Allows selection of Measurement Accuracy of Fast, Medium or Slow.
There is a tradeoff of measurement speed vs. accuracy. The meter will make a more
precise and accurate measurement at a slower rate. The speed/accuracy tradeoff is as
follows:

Fast - Measurement time of 8.333 ms (or one frequency cycle, whichever is longer),
nominal accuracy of 0.5%.

Medium - Measurement time is 125 ms, nominal accuracy of 0.25%.
Note: Above 150kHz Measurement time is 62.5 ms

Slow - Measurement time is 1 sec, nominal accuracy of 0.05%.
Note: Above 150kHz Measurement time is 0.5 s
NOTE:
Measurement times may be longer depending on frequency and other test conditions.
One complete cycle of stimulus voltage is required for measurement.
For example: at 10 Hz, 100 ms (1 cycle) is required just to collect data.
2.6.9 Measurement Delay
Accepts entry of a delay time between 0 and 1000 in 1 ms steps. This is a programmable
delay time from the internal or external trigger command to the start of the measurement.
In many cases it is helpful to have a time delay before actually starting to take data. Such
a delay allows time for switching transients or mechanical handling to settle.
2.6.10 # to Average
Accepts entry of the number of measurements to Average between 1 and 1000. If the
entered value is 1, averaging is disabled and the display is updated with each individual
measurement. If the average is 2 to 1000 the final average value is displayed at the end
of the measurement cycle and held until the end of the next measurement cycle.
Measurement accuracy can be improved as noted below and will be indicated on the
AutoAcc display (but never less than 0.05% for primary parameter or 0.0005 for
secondary parameter).
If the number to average is greater than 1:
Divide the primary accuracy by the square root of the number to average.
Divide the secondary accuracy by the square root of the number to average.
2.6.11 Contact Check
Allows selection of Contact Check Off or On. When on, any detection of contact failure
or open circuit to the device under test will be indicated prior to the measurement. A
contact failure is considered to be an open circuit greater than the open circuit calibration
of the instrument.
Contact Check is generally recommended in automatic
handler/production type applications with the 7600 Plus. For Contact Check
operation, the Range Hold must be selected ON.
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NOTE:
A contact check is possible on three of the four Kelvin connections by a loss of voltage
detecting technique, a failure on the PL connection can't be detected since it is at virtual
ground potential, internal to the instrument. The contact check is likely to be unreliable
when measuring devices of less than 100 m of impedance.
2.6.12 I/O Menu
Setup
I/0
Display Type
Nominal Value
Result Format
Trigger
Handler
RS-232
IEEE
Print Results
Results to USB
Analysis
Utilities
>>
= 1.0000
Sci
Eng
Int
Ext
Off
On
>>
>>
On
Off
On
Off
Figure 17 I/O Menu
The second of the four main menus is I/O, shown above. Each function controls
measurement results or instrument I/O interface and is described in detail below.
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7600 Plus LCR Meter
Setup
151053 A4
I/O
Analysis
Utilities
Display Type
Nominal Value - (numeric entry)
Result Format - Sci
- Eng
Trigger - Int
- Ext
Handler - Off
- On
RS-232
Measured Parmeters
Deviation from Nominal
% Deviation from Nominal
Pass/Fail
Bin Summary
Bin Number
No Display
Baud - 12
- 24
Parity - None
- 48
- Odd
- 96
Data Bits - 7
- Even
-8
Stop Bits - 1
-2
Mode - Talk
- Talk/Listen
State - Disable
- Enable
Address - (numeric entry)
IEEE
Print Results - Off
- On
Mode - Talk
- Talk/Listen
Print Results to USB
2.7
- Off
- On
State - Disable
- Enable
Display Type
Setup
I/0
Display
Analysis
Utilities
>>
Measured Paramters
Deviation from Nominal
% Deviation from Nominal
Pass / Fail
Bin Summary
Bin Number
No Display
HIT MENU TO RETURN TO MAIN MENU
Figure 18 Display Type
Allows selection from seven different modes of measurement display, these being:
29
7600 Plus LCR Meter
151053 A4
2.7.1 Measured Parameters -
Display is the measured values of both the primary and secondary parameter, displayed
along with decimal point and units. Each value is shown with 7 digits of resolution (6
digits if the result is negative). The message Measuring is shown when a measurement
is in process, with the exception of short measuring times.
Shown only when
Load Correction is on
COMP
ON
Measured Parameters
Voltage
Cs
DF
RETST
17.52510 pF
0 .0006500
Measuring
Freq
Range
Delay
1.0000kHz
Auto 33
0 ms
AC Signal
Average
Bias
1.000V
1
Off
Figure 19 Measured Parameters Display
2.7.2 Deviation from Nominal –
Display is the difference in value above or below a stored nominal value for the primary
parameter. It should be noted that the nominal value is only shown in this display and the
% Deviation display.
Deviation from Nominal
Voltage
2.8804
pF
DF 0.0006500
Freq
Range
Delay
Nominal
1.0000kHz
Auto 33
0 ms
82.00000 p
AC Signal
Average
Bias
1.000V
1
Off
Figure 20 Deviation from Nominal Display
2.7.3 % Deviation from Nominal –
Display is the measurement in terms of a percent difference above or below (-) a stored
nominal value. It should be noted that the nominal value is only shown in this display
and the Deviation from Nominal display.
30
7600 Plus LCR Meter
151053 A4
% Deviation from Nominal
Voltage
2.59417 %
0.0006500
DF
Freq
Range
Delay
Nominal
1.0000kHz
Auto 33
0 ms
82.00000 p
AC Signal
Average
Bias
1.000V
1
Off
Figure 21 % Deviation from Nominal Display
2.7.4 Pass/Fail –
Display is measured results as a pass or fail only based on entered binning limits.
Pass / Fail
Voltage
Rs 2.894050 M
Q 1.565000
PASS
1.0000kHz
Auto 33
0 ms
Freq
Range
Delay
AC Signal
Average
Bias
1.000V
1
Off
Figure 22 PASS/FAIL
2.7.5 Bin Summary –
Display is a summary of the entered bin limits and the total number of measurements
made which meet the requirements of that bin since the bin counter was last reset.
Bin
Low LIMIT
High LIMIT
Total
1
2
3
4
5
11
12
13
14
15
90.00 k 
100.00 k 
110.00 k 
120.00 k 
130.00 k 
PRI Pass SEC Fail LOW
PRI Pass SEC Fail HI
PRI Fail SEC Pass
PRI Fail SEC Fail
NO CONTACT
110.00 k
120.00 k
130.00 k
140.00 k
150.00 k





250
100
90
80
75
60
55
50
20
5
Pass
Fail
Totals:
595
190
785
Figure 23 Bin Summary Display
31
7600 Plus LCR Meter
151053 A4
2.7.6 Bin Number –
Display is a bin assignment, along with the currently programmed test conditions, for the
most recent measurement result.
Bin Number
Voltage
10
Freq
Range
Delay
1.0000kHz
Auto 33
0 ms
AC Signal
Average
Bias
1.000V
1
Off
Figure 24 Bin Number Display
2.7.7 No Display –
Instrument display is inhibited from indicating any measurement results. This is
sometimes used for security reasons or for the purpose of reducing test time during
remote operation.
2.7.8 Nominal Value
Allows entry of a Nominal Value for the primary parameter, which is the basis for the
measurement result in Deviation or % Deviation. Accepts numerical entry up to
seven digits with decimal. Units are selected by the UP/DOWN arrow keys and
determined by the primary parameter selection, i.e. in Farads, Ohms, Henries, etc.
NOTE:
The nominal value has no relationship to nominal values entered during binning
setup.
2.7.9 Result Format
Allows selection from two different measurement result formats SCI and ENG, for
scientific or engineering units. Scientific units are expressed as an exponent and
engineering units are expressed in ohms for resistance, farads for capacitance, henries for
inductance, etc. For example e3 in scientific units can be expressed as k in engineering
units; or e-3 in scientific units can be expressed as m in engineering units, this is
strictly user preference and convenience.
When scientific units are selected the results will always be displayed as some number of
digits with decimal, exponent and units. When engineering units is selected the results
will be displayed as some number of digits with decimal and units.
2.7.10 Trigger
Allows selection of two trigger modes, Internal or External.
32
7600 Plus LCR Meter
151053 A4

Internal - Measurement trigger is automatic and continuous once initiated with a
START. If the STOP key is pressed in the middle of a measurement (with Range
Hold set to OFF) any measurement range indication or displayed results is invalid.

External - Measurement trigger is under remote control via front panel, handler, RS
232 or IEEE-488 interface.
2.7.11 Handler Interface
Allows user to turn Handler Interface function On or Off. When On is selected the input
and output lines on the rear panel I/O interface connector are acknowledged. When Off is
selected they are ignored.
2.7.12 RS-232 Interface
Setup
I/0
RS-232
Baud
Parity
Data Bits
Stop Bits
Mode
State
Analysis
Utilities
>>
12
24
48
96
Odd
Even
None
7
8
2
1
Talk
Talk/Listen
Disable Enable
HIT MENU TO RETURN TO MAIN MENU
Figure 25 RS-232 Setup Format
Allows user setup of standard RS-232 interface formats. Choices include:
Baud Rate - 12, 24, 48, or 96 (for 1200, 2400, 4800, and 9600 respectively)
Parity
- None, Even or Odd
Data Bits
- 7 or 8
Stop Bits
- 1 or 2
Mode
- Talk or Talk/Listen
UP/DOWN arrow and Enter selects the desired format and then LEFT/RIGHT arrow
and ENTER allows for selection of choices within each format.
33
7600 Plus LCR Meter
151053 A4
2.7.13 IEEE-488.2 Interface for use with 7000-22 (Discontinued)
Setup
I/0
IEEE
Analysis
Address = 4
Talk
Mode
State
Disable
Utilities
>>
Talk/Listen
Enable
HIT MENU TO RETURN TO MAIN MENU
Figure 26 IEEE Setup Format
Note: IEEE Interface is an Option. If option is not installed, State cannot be
enabled.
Allows user setup of IEEE-488 interface format. Choices include:
Address
- 1 through 16
Mode
- Talk or Talk/Listen
State
- Disable or Enable
UP/DOWN arrow and ENTER selects the desired format and then LEFT/RIGHT arrow
and ENTER allows for selection of choices within each format.
The instrument will function as either a Talk or a Talk/Listen device in a system
depending on the choice made by the operator under Mode. Talk is generally suited to a
simple system with no controller or other talkers, for example a printer. Talk/Listen
denotes full programmability and is suited for use in a system that has a controller or
computer to manage data flow. The "handshake" routine assures that the active talker
proceeds slowly enough for the slowest listener.
2.7.14 Print Results
Allows user to output results to the parallel port by selection of Off or On. Before
selecting On make sure the printer is connected and on-line.
File format for printing is the same as shown in the next paragraph under Results to
USB. Lines not printed are indicated.
2.7.15 Results to USB
The 7600 Plus can be used with most USB memory sticks, mass storage class,
FAT16/FAT32 format; maximum consumption current must be below 500 mA. The
memory stick can be installed and removed at anytime. The USB stick is automatically
mounted when installed. The USB host port complies with USB v2.0 standard. The
USB host port is not designed to be connected to a PC, Printer or USB hub.
34
7600 Plus LCR Meter
151053 A4
Allows user to store measurement results on flash drive. If a results file is not open, the
user is prompted for the filename (up to 8 characters) and the file is opened.
To close a results file that is currently open, select Results to USB and close.
If a results file is open when a setup is saved, when the setup is later recalled the user will
be prompted for a results file name.
When multiple tests are being conducted the results are stored to USB periodically (every
10 measurements) from an internal buffer. To be sure of storing all results before
power is shut down the file needs to be closed as discussed earlier. It is also important
to note that a file should be closed before changing or recalling a new set of test
conditions, otherwise the stored measurement results would not be consistent with the
setup conditions stored in the file.
The measurement results are stored as an comma separated ASCII text file under its
assigned identifying number (up to 8 characters). The extension for Data is “.csv”
The test setup conditions are saved as a header at the beginning of a results file. A
sample file format is shown below. Note that the results can be stored in either
engineering or scientific terms dependent on what the user has selected for setup
conditions. The format of the result string is as follows:
Label, Primary result, Units, Label, Secondary result, Units, Bin#<CR><LF>
Sample file format as follows.
Copyright IET Labs Inc. 2008
not printed
ENDHEADER
not printed
2000000.000000
;frequency
5.000000
;primary parameter
2.000000
;secondary parameter
0.000000
;ac signal type
0.100000
;ac signal value
0.000000
;bias
0.000000
;range
1.000000
;rangelocked
68.000000
;range relay
not printed
205.000000
;relay 2
|
69.000000
;relay 3
|
66.000000
;va
not printed
2.000000
;measurment speed
0.000000
;delay time
1.000000
;# to average
0.000000
;contact check
35
7600 Plus LCR Meter
0.000000
151053 A4
;display type
0.00000000009989577000
;nominal value
0.000000
;result format
1.000000
;trigger
1.000000
;handler
3.000000
;baud
0.000000
;parity
1.000000
;data bits
0.000000
;stop bits
1.000000
;rs232 mode
1.000000
;rs232 state
4.000000
;IEEE address
1.000000
;IEEE mode
0.000000
;IEEE state
0.000000
;print results
0.000000
;result to USB
0.00000000000000000000
;low limit bin 0
0.00000000000000000000
;high limit bin 0
0.00000000000000000000
;nominal value bin 0
0.000000
;low limit bin 1
0.00000000000000000000
;high limit bin 1
0.00000000000000000000
;nominal value bin 1
;low limit bin 2
0.00000000000000000000
;high limit bin 2
0.00000000000000000000
;nominal value bin 2
;low limit bin 3
0.00000000000000000000
;high limit bin 3
0.00000000000000000000
;nominal value bin 3
|
|
|
|
|
|
|
|
|
|
|
;limit format bin 3
0.00000000000000000000
;low limit bin 4
0.00000000000000000000
;high limit bin 4
36
|
;limit format bin 2
0.00000000000000000000
0.000000
|
;limit format bin 1
0.00000000000000000000
0.000000
|
;limit format bin 0
0.00000000000000000000
0.000000
not printed
|
|
|
7600 Plus LCR Meter
151053 A4
0.00000000000000000000
0.000000
;nominal value bin 4
;limit format bin 4
0.00000000000000000000
;low limit bin 5
0.00000000000000000000
;high limit bin 5
0.00000000000000000000
;nominal value bin 5
0.000000
;low limit bin 6
0.00000000000000000000
;high limit bin 6
0.00000000000000000000
;nominal value bin 6
;low limit bin 7
0.00000000000000000000
;high limit bin 7
0.00000000000000000000
;nominal value bin 7
;low limit bin 8
0.00000000000000000000
;high limit bin 8
0.00000000000000000000
;nominal value bin 8
|
|
|
|
|
|
|
|
|
|
|
|
|
;limit format bin 8
0.00000000000000000000
;low limit bin 9
0.00000000000000000000
;high limit bin 9
0.00000000000000000000
;nominal value bin 9
0.000000
|
;limit format bin 7
0.00000000000000000000
0.000000
|
;limit format bin 6
0.00000000000000000000
0.000000
|
;limit format bin 5
0.00000000000000000000
0.000000
|
;limit format bin 9
|
|
|
|
|
0.00000000000000000000
;low limit bin 10
|
0.00000000000000000000
;high limit bin 10
|
0.00000000000000000000
;nominal value bin 10
|
0.000000
;limit format bin 10
|
0.00000000000000000000
;low limit bin 11
|
0.00000000000000000000
;high limit bin 11
|
0.00000000000000000000
;nominal value bin 11
|
0.000000
;limit format bin 11
|
0.00000000000000000000
;low limit bin 12
|
0.00000000000000000000
;high limit bin 12
|
0.00000000000000000000
;nominal value bin 12
|
0.000000
;limit format bin 12
|
37
7600 Plus LCR Meter
151053 A4
0.00000000000000000000
;low limit bin 13
|
0.00000000000000000000
;high limit bin 13
|
0.00000000000000000000
;nominal value bin 13
|
0.000000
;limit format bin 13
|
0.00000000000000000000
;low limit bin 14
|
0.00000000000000000000
;high limit bin 14
|
0.00000000000000000000
;nominal value bin 14
|
0.000000
;limit format bin 14
0.000000
;secondary low
0.000000
;secondary high
0.000000
;sequence
0.000000
;sequence status
1000.000000
;sequence frequency
|
0.000000
;sequence pri param
|
0.000000
;sequence sec param
|
0.000000
;sequence bias
|
0.000000
;sequence ac signal type
1.000000
;sequence ac signal value
0.000000
;sequence delay
|
0.000000
;sequence range
|
0.000000
;sequence range relay
|
0.000000
;sequence relay 2
|
0.000000
;sequence relay 3
|
0.000000
;sequence var relay
|
1.000000
;sequence stop on fail
|
0.000000
;sequence status
1000.000000
;sequence frequency
|
0.000000
;sequence pri param
|
0.000000
;sequence sec param
|
0.000000
;sequence bias
|
0.000000
;sequence ac signal type
1.000000
;sequence ac signal value
0.000000
;sequence delay
|
0.000000
;sequence range
|
38
not printed
printed only if sequence enabled
|
|
|
|
|
7600 Plus LCR Meter
151053 A4
0.000000
;sequence range relay
|
0.000000
;sequence relay 2
|
0.000000
;sequence relay 3
|
0.000000
;sequence var relay
|
1.000000
;sequence stop on fail
|
0.000000
;sequence status
1000.000000
;sequence frequency
|
0.000000
;sequence pri param
|
0.000000
;sequence sec param
|
0.000000
;sequence bias
|
0.000000
;sequence ac signal type
1.000000
;sequence ac signal value
0.000000
;sequence delay
|
0.000000
;sequence range
|
0.000000
;sequence range relay
|
0.000000
;sequence relay 2
|
0.000000
;sequence relay 3
|
0.000000
;sequence var relay
|
1.000000
;sequence stop on fail
|
0.000000
;sequence status
1000.000000
;sequence frequency
|
0.000000
;sequence pri param
|
0.000000
;sequence sec param
|
0.000000
;sequence bias
|
0.000000
;sequence ac signal type
1.000000
;sequence ac signal value
0.000000
;sequence delay
|
0.000000
;sequence range
|
0.000000
;sequence range relay
|
0.000000
;sequence relay 2
|
0.000000
;sequence relay 3
|
0.000000
;sequence var relay
|
1.000000
;sequence stop on fail
|
0.000000
;sequence status
|
|
|
|
|
|
|
39
7600 Plus LCR Meter
151053 A4
1000.000000
;sequence frequency
|
0.000000
;sequence pri param
|
0.000000
;sequence sec param
|
0.000000
;sequence bias
|
0.000000
;sequence ac signal type
1.000000
;sequence ac signal value
0.000000
;sequence delay
|
0.000000
;sequence range
|
0.000000
;sequence range relay
|
0.000000
;sequence relay 2
|
0.000000
;sequence relay 3
|
0.000000
;sequence var relay
|
1.000000
;sequence stop on fail
|
0.000000
;sequence status
1000.000000
;sequence frequency
|
0.000000
;sequence pri param
|
0.000000
;sequence sec param
|
0.000000
;sequence bias
|
0.000000
;sequence ac signal type
1.000000
;sequence ac signal value
0.000000
;sequence delay
|
0.000000
;sequence range
|
0.000000
;sequence range relay
|
0.000000
;sequence relay 2
|
0.000000
;sequence relay 3
|
0.000000
;sequence var relay
|
1.000000
;sequence stop on fail
|
0.000000
;sweep
0.000000
;sweep parameter
10.000000
;sweep begin
1000.000000
;sweep end
0.000000
;sweep step
0.000000
;sweep result format
0.000000
;median
40
|
|
|
|
|
printed only if sequence enabled
7600 Plus LCR Meter
151053 A4
1.000000
;correction
25.000000
;correction primary nominal
50.000000
;correction secondary nominal
1.000000
;correction status
1000.000000
;correction frequency
49.000000
;correction range
5.000000
;correction primary parameter
4.000000
;correction secondary parameter
25.17072 
;correction measured primary
-.1947500
;correction measured secondary
-0.170725
;correction primary correction
50.194742
;correction secondary correction
0.000000
;enhanced distortion
0.000000
;lockout
1.000000
;backlite
ENDHEADER
Cs, 9.69573e-09, F, DF, 0.0052921, Bin, 1,,,,
Cs, 9.69645e-09, F, DF, 0.0052307, Bin, 1,,,,
Cs, 9.69575e-09, F, DF, 0.0052404, Bin, 1,,,,
Cs, 9.69583e-09, F, DF, 0.0052983, Bin, 1,,,,
Cs, 9.69698e-09, F, DF, 0.0053328, Bin, 1,,,,
The number of measurement results that can be stored is dependent on available memory
and length of the data string. For example; if no limit is set the measurement string
contains no bin results, thus the string has fewer characters. The same is true with header
information: multiple headers (different test conditions) will consume more memory.
2.7.16 Analysis Menu
Setup
I/0
Analysis
Binning
Test Sequencing
Parameter Sweep
Median
Distort Detect
Load Correction
Off
Off
Off
Off
Off
Utilities
On
On
On
On
On
>>
Edit
Edit
Edit
41
7600 Plus LCR Meter
151053 A4
Figure 27 Analysis Menu
The third of the four main menus is Analysis, shown above. Each function controls the
analysis of measurement results and is described in detail below.
Setup
I/O
Analysis
Utilities
Binning
Absolute Limit - Bin #
- Low Limit
Tolerance % - Bin #
- High Limit
Secondary Low - (numeric entry) - Nominal
- % Below
Secondary High - (numeric entry) - % Above
View Bin Totals
Zero Bin Totals
Test Sequencing - Off
- On
- Edit
Parameter Sweep - Off
- On
- Edit
Median - Off
- On
Distort Detect
- Off
- On
Load Correction - Off
- On
- Edit
42
7600 Plus LCR Meter
151053 A4
2.7.17 Binning
Setup
I/0
Analysis
Binning
Absolute Limit
Tolerance %
Secondary Low
Secondary High
View Bin Totals
Zero Bin Totals
Utilities
>>
>>
>>
= 0.000000
= 0.000000
>>
>>
HIT MENU TO RETURN TO MAIN MENU
Figure 28 Binning
The 7600 Plus provides sorting into 15 bins (10 pass, 4 fail and 1 for no contact). For the
binning function to be enabled, one or both of the two conditions must be met:
1. Bin 1 limits must be set (non-zero).
2. Secondary parameter must be set (not NONE) and secondary low/high limits must be
set (non-zero).
These are assigned as follows:
Bins 1 through 10 - Pass bins for the primary parameter (Pass for secondary
parameter if limit is entered)
Bin 11 - Primary parameter pass and secondary parameter fail low
Bin 12 - Primary parameter pass and secondary parameter fail high
Bin 13 - Primary parameter fail and secondary parameter pass
Bin 14 - Primary parameter fail and secondary parameter fail
Bin 15 - No contact
Note:
If no limit is entered for primary parameter but one is for the secondary
parameter, bin assignment will be to Bin 1 for a pass, Bin 11 for a fail low, or Bin
12 for a fail high.
Bin assignment during the test sequencing mode of operation is entirely different.
Bin limits for the primary parameter can be entered in terms of absolute value or as a
percent tolerance about a defined nominal. Two of the most common methods sorting is
nested limits and sequential limits. Nested limits are a natural choice for sorting by %
tolerance around a single nominal value with the lower number bins narrower than the
higher numbered ones. Nested limits for three bins is illustrated below, note that limits
do not have to be symmetrical as shown for bin 3.
43
7600 Plus LCR Meter
151053 A4
Bin 3
Bin 2
Bin 1
Measured
Value
Axis
N
-1%
+1%
-5%
+5%
-7%
+10%
Nominal Value
100.00 k 
Tolerance Percent
Bin
Nominal
1
2
3
100.00 k
100.00 k
100.00 k
% BELOW
% ABOVE
1.00
5.00
10.00
1.00
5.00
7.00
Sequential limits are a natural choice for sorting by absolute value. Sequential limits for
three bins are illustrated below. It should be noted that the bins do not necessarily have
to be adjacent. Depending on the specified limits for each they can be overlapping,
adjacent or even isolated (gaps) from each other. Any overlap is assigned to the lower
numbered bin and a gap would be assigned to the overall fail bin.
Bin 1
Bin 2
85.00 k  90.00 k 
Bin 3
100.00 k 
Measured
Value
Axis
120.00 k 
Absolute Limit
Bin
Low LIMIT
High LIMIT
1
2
3
85.00 k
90.00 k
100.00 k
90.00 k
100.00 k
120.00 k
2.7.18 Absolute Limit
Absolute limit selection allows for entry of both upper and lower limit for each bin in
absolute value. Valid range for each is -108 to 109. If zero is entered for Low or
High, the previous value is cleared and that bin disabled. When limits are entered in
terms of absolute value the same limits will automatically be shown in terms of percent
on the Tolerance Percent Display. This automatic calculation should be used cautiously;
imprecise displays and missed bin assignments are possible at the range extremes. Arrow
up, down, left to right to select the limit of interest in either the low or high limit column
as shown below (low limit for bin 5 is chosen in this example)
44
7600 Plus LCR Meter
151053 A4
Absolute Limit
Bin
Low LIMIT
High LIMIT
1
2
3
4
5
6
7
8
9
10
90.00 k
100.00 k
110.00 k
120.00 k
130.00 k
140.00 k
150.00 k
160.00 k
170.00 k
180.00 k
110.00 k
120.00 k
130.00 k
140.00 k
150.00 k
160.00 k
170.00 k
180.00 k
190.00 k
120.00 k
Figure 29 Absolute Limit
Once the limit of choice is selected by UP/DOWN, LEFT/RIGHT arrow and ENTER
the numerical value can be entered directly as shown below (entry is 130 in this
example).
Absolute Limit
Bin
Low LIMIT
High LIMIT
1
2
3
4
5
6
7
8
9
10
90.00 k
100.00 k
110.00 k
120.00 k
130
140.00 k
150.00 k
160.00 k
170.00 k
180.00 k
110.00 k
120.00 k
130.00 k
140.00 k
150.00 k
160.00 k
170.00 k
180.00 k
190.00 k
200.00 k
Figure 30 Absolute Limit (Numeric Entry)
Then arrow up or down to select units from those available (k is chosen in this example).
Absolute Limit
Bin
Low LIMIT
High LIMIT
1
2
3
4
5
6
7
8
9
10
90.00 k
100.00 k
110.00 k
120.00 k
130 k
140.00 k
150.00 k
160.00 k
170.00 k
180.00 k
110.00 k
120.00 k
130.00 k
140.00 k
150.00 k
160.00 k
170.00 k
180.00 k
190.00 k
120.00 k
Figure 31 Absolute Limit (Engineering Units)
Press ENTER to finalize the entry, the UP/DOWN, LEFT/RIGHT arrow to choose the
next limit to be entered or changed.
45
7600 Plus LCR Meter
46
151053 A4
7600 Plus LCR Meter
151053 A4
2.7.19 Tolerance Percent
Tolerance Percent selection allows for entry of both upper and lower limit in terms of
percent below or above an entered nominal (both must be entered). When limits are
entered in terms of percent the same limits will automatically be shown in terms of
absolute value on the Absolute Value Display. Arrow up, down, left to right to select the
nominal value or % limit of interest as shown below. The nominal value can be entered
in the same fashion as the absolute limit is entered above, numerical value, then arrow Up
or Down to select units. Valid range is -108 to 109. If zero is entered for Nominal, the
entire row is cleared and that bin disabled. The % tolerance can be entered directly in
increments of 0.01%, any increments smaller than this are rounded to the closest 0.01%.
Valid range for each is 0 to 100. If zero is entered for %Below or %Above, the
previous value is cleared and that bin disabled.
Tolerance Percent
Bin
Nominal
% BELOW
% ABOVE
1
2
3
4
5
6
7
8
9
10
100.00 k
110.00 k
120.00 k
130.00 k
140.00 k
150.00 k
160.00 k
170.00 k
180.00 k
190.00 k




















Figure 32 Tolerance Percent
2.7.20 Secondary Low
Accepts entry of numerical value for the low limit of the secondary parameter. Units are
determined by the secondary parameter selection, i.e. in Farads, Ohms, Henries, etc. and
selected by the UP/DOWN arrow keys. Valid range is -103 to 104.
NOTE:
Low limit must be less than the High limit
2.7.21 Secondary High
Accepts entry of numerical value for the high limit of the secondary parameter. Units are
determined by the secondary parameter selection, i.e. in Farads, Ohms, Henries, etc. and
selected by the UP/DOWN arrow keys. Valid range is -103 to 104.
NOTE:
High limit must be greater than the Low limit
47
7600 Plus LCR Meter
151053 A4
2.7.22 View Bin Totals
Bin
1
2
3
4
5
11
12
13
14
15
Totals:
Low LIMIT
High LIMIT
90.00 k
100.00 k
110.00 k
120.00 k
130.00 k
PRI Pass SEC Fail LOW
PRI Pass SEC Fail HI
PRI Fail SEC Pass
PRI Fail SEC Fail
NO CONTACT
Pass 595
110.00 k
120.00 k
130.00 k
140.00 k
150.00 k
Fail
Total
250
100
90
80
75
60
55
50
20
5
190
785
HIT MENU TO RETURN TO MAIN MENU
Figure 33 Bin Totals
The total count for each bin is tracked from 0 to 999,999.
2.7.23 Zero Bin Totals
Bin count totals are all reset to zero when selected and returned to the Menu screen.
2.7.24 Test Sequencing
The 7600 Plus is capable of performing a sequence measurement containing up to six
different test steps. Different measurement parameters and conditions can be defined
for each test in the sequence.
Test sequencing can be selected as Off, On or Edit. Edit allows measurement
parameters and test conditions to be changed for all six tests. It is important to note that
tests can only be enabled in sequence, for example, one can enable tests 1 through 3 but
not tests 1 and 3 only, i.e. it is not possible to skip a test. For optimum measure speed
performance, whenever possible, set test conditions of test 1 to be the same as default
conditions.
Sequence Setup Test 1
Test 1 Status
Primary Parameter
Secondary Parameter
Frequency
DC Bias Voltage
AC Signal Type
AC Signal Value
Measurement Delay (ms)
Range Hold
Stop on Fail
Binning
Disable
Enable
>>
>>
= 1.0000kHz
Off
Int
Voltage
= 1.000 V
=0
Off
On
Off
On
Ext
Current
Prev
Test
>>
HIT MENU TO RETURN TO MAIN MENU
Figure 34 Sequence Setup (Test Conditions)
48
Next
Test
7600 Plus LCR Meter
151053 A4
If Range Hold is turned ON and this is the "first" sequence measurement, for each test the
7600 Plus automatically finds the correct range and completes a measurement (this range
is saved for all future measurements) for that sequence only. It is important that the first
part be "good" for the range hold to select the correct range. To repeat an auto range
selection, turn sequences off and then back on again (making the next measurement taken
the "first" sequence measurement).
Test conditions for each setup are selected as shown above except for the primary
parameter, secondary parameter and binning, these are selected on individual menus as
shown below. To change test conditions on any or all six tests select Prev Test or Next
Test to access test conditions for that test.
Sequence Setup Test 1
Pri Param
Auto
Cs
Cp
Ls
Lp
Rs
Rp
DF
Q
|Z|
|Y|
HIT MENU TO RETURN TO MAIN MENU
Figure 35 Sequence Setup (Parameter Selection)
Bin assignment in the test sequence mode is defined as follows:
Bin #
Assigned
Bin 1
Test 1 (Primary parameter, fail)
Bin 2
Test 1 (Secondary parameter, fail)
Bin 3
Test 2 (Primary parameter, fail)
Bin 4
Test 2 (Secondary parameter, fail)
Bin 5
Test 3 (Primary parameter, fail)
Bin 6
Test 3 (Secondary parameter, fail)
Bin 7
Test 4 (Primary parameter, fail)
Bin 8
Test 4 (Secondary parameter, fail)
Bin 9
Test 5 (Primary parameter, fail)
Bin 10
Test 5 (Secondary parameter, fail)
Bin 11
Test 6 (Primary parameter, fail)
Bin 12
Test 6 (Secondary parameter, fail)
Bin 13
Unused
Bin 14
Pass Bin
Bin 15
Contact Check, fail
49
7600 Plus LCR Meter
151053 A4
For the binning function to be enabled, Bin 1 limits must be set (non-zero). If zero is
entered for Low or High, the previous value is cleared and that bin disabled. Valid
range for primary or secondary is -108 to 109. All sequence binning limits must be
entered on the display shown below and NOT the standard binning displays.
Sequence Setup Test 1
Bin
Low LIMIT
High LIMIT
1 Pri
2 Sec
90.00 k
100.00 k
110.00 k
120.00 k
Figure 36 Sequence Binning
Test conditions of measurement sequences can be stored and/or recalled as part of test
setups. If a test sequence is stored as On, the sequence will be executed once the Start
button is pressed, if the test sequence is stored as Off, the sequence will be inactive until
turned on.
Note that a sequence (of up to six tests) can be terminated on any test of the sequence if
the user has specified Stop on Fail for that test. If Stop on Fail is not selected the
sequence continues until a failure occurs in a test where Stop on Fail has been enabled or
until the whole sequence has been completed. Once a sequence is complete, it will be
binned to the first fail bin (1 thru 12) or if all tests pass, binned into the overall pass bin
(14).
When a test sequence is turned on the results of the sequence are shown on the summary
screen shown below. Measured values outside of specified limits are highlighted.
Sequence Results
FAIL
BIN
5
Test 1
Cs
1.561062 uF
DF
0.0089290
Test 2
Cs
1.498650 uF
DF
0.0078950
Test 3
Cs
1.278650 uF
DF
0.0067994 FAIL
Figure 37 Sequence Results
50
7600 Plus LCR Meter
2.8
151053 A4
Parameter Sweep
The 7600 Plus is capable of displaying a table or plot of measured results vs. a
variable of frequency, voltage, or current.
Sweep can be selected as Off, On or Edit. Edit allows sweep test conditions to be
changed.
Setup
I/0
Analysis
Sweep
Parameter
Sweep Begin
Sweep End
Sweep Step
Sweep Format
Utilities
>>
Freq Voltage Current
= 10.0 Hz
= 1.0000 kHz
50 100 200
25
Plot
Table
HIT MENU TO RETURN TO MAIN MENU
Figure 38 Parameter Sweep
Parameter is the variable test condition of Frequency, Voltage or Current.
Sweep Begin is the lower boundary of the sweep table or plot in units of Hz, Volts or
Amps. The numerical value is entered directly and units selected by UP/DOWN arrow
keys.
Sweep End is the upper boundary of the sweep in units of Hz, Volts or Amps and
entered the same as Sweep Begin.
Sweep Step is the chosen number of increments in a sweep of 25, 50 100 or 200 where
values are automatically selected, logarithmically over the specified begin to end range.
Sweep Format is selected to be Table as shown in Figure 39 or Plot as shown in Figure
40.
Plot Table
Frequency
Cs
1.0000kHz
1.2915kHz
1.6681kHz
2.1544kHz
2.7825kHz
3.5938kHz
4.6415kHz
5.9948kHz
7.7426kHz
10.000kHz
471.4576nF
470.4563nF
469.8878nF
468.9983nF
466.4532nF
462.6634nF
460.6645nF
459.7892nF
458.7845nF
456.5454nF
DF
0.003135
0.003675
0.003867
0.010035
0.010078
0.011045
0.012895
0.014786
0.016782
0.018544
Prev
Page
Next
Page
Figure 39 Sweep Table
51
7600 Plus LCR Meter
151053 A4
The sweep table lists the measurement results for primary and secondary parameter
(unless none is selected) along with the test condition variable of frequency, voltage or
current. A table can be comprised of 25, 50, 100 or 200 entries and the UP/DOWN
arrow keys or Prev or Next Page used to scroll through the display.
NOTE:
Scroll is not functional when IEEE-488 is enabled.
200.0
180.0
160.0
140.0
120.0
100.0
|Z| 
50.000k
51.000k
54.000k
Frequency Hz
62.000k
Figure 40 Sweep Plot
The sweep plot shows the measurement results of the primary parameter (vertical axis)
vs. the variable test condition of frequency, voltage or current (horizontal axis). It should
be noted that space available on the display limits the number of graduations and
resolution of axis labeling. The horizontal axis is labeled from the Sweep Begin to the
Sweep End values as selected by the user with two additional labels in between (chosen
logarithmically). The vertical axis is labeled from the lowest measured value to the
highest measured value with four additional labels in between (chosen linearly).
2.9
Median
Allows for the selection of Median measurement mode to be On or Off. When selected
each measurement will actually be three individual measurements, the lowest and
highest values discarded and the median value displayed.
Measurement accuracy can be improved as noted below and will be indicated on the
AutoAcc display (but never less than 0.05% for primary parameter or 0.0005 for
secondary parameter).
With Median set to On:
Divide the primary accuracy by the square root of three.
Divide the secondary accuracy by the square root of three.
2.9.1 Distortion Detection
Allows for the selection of Distortion Detection mode to be On or Off. When set to On,
the unit will detect distortion during a measurement and indicates the message
"DISTORTION" if this condition occurs. When set to Off, distortion will not be detected
during a measurement.
52
7600 Plus LCR Meter
151053 A4
Distortion is dependent on programmed test conditions, connection to the device, device
impedance and so indicated when the signal + noise + distortion divided by the signal
exceeds 1.2. Distortion set to On is the recommended test condition and is particularly
important for high precision measurements where test leads could resonate with the
device under test. Distortion may want to be turned to Off in a "noisy" environment.
To ensure that stored setups are backward compatible Distortion On or Off is not saved
in setups stored (internally or on USB flash drive). On instrument power down the
Distort Detect will be restored to its last previous state.
2.9.2 Load Correction
Load correction allows the user to specify the value of the component under test (user
supplied standard) and apply a correction to subsequent measurements of similar
components under the same test conditions. This feature corrects for instrument nonlinearity and for fixture effects which can be dependent on the test frequency, test voltage
level or impedance range.
Measurement accuracy is 0.25 x (normal accuracy) with Load Correction implemented
and compared to user supplied standard and for the same measurement conditions. (Same
measurement conditions are test voltage, test frequency and 7600 Plus measurement
range.)
This increased accuracy applies in a range of:
DUT's with impedance (Z) between 3 and 800k, with
programmed voltage from 100mV to 1V, or from 100mV
to (programmed current) x (Z) 1V.
Load correction can be selected as Off, On or Edit. Edit allows the primary and
secondary values to be entered, the parameter for these values is defined by the Primary
and Secondary Parameter in the main Setup menu. After the nominal values have been
entered, if Measure is selected for ON, the user presses START to initiate the correction
measurement. While the measurement is being made, Measuring Correction will be
displayed. After the correction measurement the actual Measured Primary and
Secondary value will be displayed along with the selected Freq, Range, Primary and
Secondary parameter. During the load correction measurement the instrument is
automatically placed in the Slow Measurement Accuracy mode.
Load Correction
Measure
Primary Nominal
Secondary Nominal
Off On
60.00000 pF
4.000000 m
Measuring Correction
Measured Primary
Measured Secondary
60.25518 pF
.0042580
Freq
1.0000MHz
Primary
Cs
Secondary DF
Range 49
HIT <START> TO MEASURE CORRECTION
HIT <ENTER> TO CHANGE VALUES
HIT <MENU> TO RETURN TO MAIN MENU
Figure 41 Load Correction
53
7600 Plus LCR Meter
151053 A4
The Load Correction will only be made for the Frequency, Range, Primary and
Secondary Parameter that was selected when the correction was determined. For
example; if the correction measurement is made under the conditions of Cs, DF, at 1
MHz and range 49, these are the only conditions under which it will be applied.
2.9.3 Utilities Menu
Setup
Analysis
I/0
Utilities
Save Setup
Recall Setup
AutoAcc
Open / Short
Lock Out
Calibration
Set Time / Date
Usage / Cal Date
Set Contrast
Self Test
Save
LCD Backlite
>>
>>
>>
>>
>>
>>
>>
>>
>>
>>
On
Figure 42 Utilities Menu
The last of the four main menus is Utilities, shown above. Each function is described in
detail below.
Setup
I/O
Analysis
Utilities
Save Setup
Recall Setup
AutoAcc tm
- delete
- delete
Open/Short
Lock Out
- Lock Out with Setup Recall
- Lock Out Only
See para. 4.4
Calibration
Set Time/Date
Usage/Cal Date
Set Contrast
Self Test
Messages
LCD Backlite - Save
- On
54
-T
-D
- Short
- Open
- Quick Open & Short
7600 Plus LCR Meter
151053 A4
2.9.4 Save Setup
Setup
I/0
Analysis
Utilities
Save
NEW
DEFAULT
USB
12345
1234
123
d
e
l
HIT MENU TO RETURN TO MAIN MENU
Figure 43 Save Setup
Allows a set of test conditions to be stored in instrument memory or on USB flash disk
for later recall. Test conditions are those that are user programmable in the Setup and I/O
menus.
To store the current set of test conditions as a new set in unit memory one needs to select
NEW in the Save Setup menu and enter the identifying name up to 8 characters under
which these conditions will be stored (allowable characters from the keypad include 0
through 9 and minus, characters can also include A through Z when operating from
remote control ). To save the setup under the name selected or to overwrite if the name
already exists one needs to answer Yes or No.
Setup
I/0
Analysis
Utilities
Y
SAVE AS 1234?
N
Figure 44 Yes or No
To make the current set of test conditions the default (at power up) one needs to select
DEFAULT in the Save Setup menu and overwrite the conditions currently stored. To
prevent overwriting the default setup by mistake an additional level of safety exists
where the operator is required to respond with Yes or No.
Selecting del will delete a set of test conditions and requires a Yes or No response.
When there are more setups than can fit on the display the page down key is active. If
there is less than a whole page below, the display wraps around to the previous display.
55
7600 Plus LCR Meter
151053 A4
Continuing to page down will eventually return to the first display of setups. The page
down key is only shown when there are more setups than what is visible.
There are two ways to make the current set of test conditions overwrite an existing setup,
one is to select that setup in the menu and answer Yes to overwrite and the other way is
to enter the same name under New and answer Yes to overwrite.
File format for storing test conditions is the same as shown under Results to USB (page
34), all lines shown are saved as setup. The extension of a Setups file is “.c6r”. The
setup files are compatible with 7600 Model B. The only difference is the extension.
Changing the extension from Model B files to “.c6r” will allow files to be recalled in the
7600 Plus.
2.9.5 Recall Setup
Setup
I/0
Analysis
Utilities
Recall
DEFAULT
USB
12345
1234
123
d
e
l
HIT MENU TO RETURN TO MAIN MENU
Figure 45 Recall Setup
Allows a previously stored set of test conditions to be recalled from instrument memory.
Test conditions are those that are user programmable in the Setup and I/O menus. To
recall a set of test conditions one needs to arrow down or up to the desired set.
DEFAULT is always one of the set of test conditions that can be recalled as discussed in
the previous paragraph. Selecting del will delete a set of test conditions and requires a
Yes or No response.
When there are more setups than can fit on the display the page down key is active. If
there is less than a whole page below, the display wraps around to the previous display.
Continuing to page down will eventually return to the first display of setups.
2.9.6 Setup Accuracy
Allows user to access the measurement calculation. Calculated accuracy is displayed for
the instruments currently selected test conditions, as shown in the example below and in
accordance with the formulas for fast, medium or slow accuracy. Factors affecting
this calculation include frequency, ac test signal level, measurement accuracy and # to
average, all test conditions under operator control on the Setup Menu. The selection of
Median, on the Analysis Menu, also has an affect on the accuracy calculation.
The Accuracy, Average and Median can be changed on this screen as instructed for the
purpose of evaluating their effect on the instrument accuracy calculation and the changes
implemented if the operator so chooses. The frequency, AC signal or parameter selection
56
7600 Plus LCR Meter
151053 A4
can only be changed on the Setup menu. In summary, this display shows instrument
accuracy for currently selected test conditions or as a tool so the operator can see
what the accuracy would be if certain conditions were selected.
AutoAcc tm
Accuracy Slow
Average
1
Median
Off
On
Freq
1.0000kHz
AC Signal 1.000 V
Arrow keys to select parameters
ENTER key to change the values
START key to calculate accuracy
Accuracy as Configured
.075%
.0005000
Cs
DF
Figure 46 Setup Accuracy
The basis for the AutoAcc calculation is based on the formulas below where A% =
calculated primary accuracy for C, X, B with D  0.1 and R, L, G with Q  0.1 for
optimum signal levels and test conditions.
For C, X, and B, with D > 0.1, multiply A% by 1  D 2
1  Q2
For R and G, with Q > 0.1, multiply A% by
For L, with Q < 10, multiply A% by
1 1
Q2
Multipliers do not apply to 1 MHz Special Case Accuracy
For Fast Mode, R, L, C, X, G, B, |Z|, and |Y|


.125
A%   0.25    0.25 
 Z m *10  6

Z

m


 *  0V.2  0.8 * VV
fs
 
s

Vs  12  *  0.4 
 
 
4
s
Fm 400   
  * Kt

10 4 Fm   

For Medium Mode, R, L, C, X, G, B, |Z|, and |Y|


.1
A%   0.125    0.125 
 Z m *10 6

Z

m


 *  0V.2  0.8 * VV
fs
 
s

Vs  12 

Fm
300  
 0.4 
  * Kt
*


3 *10 4 Fm  
 
4
s
For Slow Mode, R, L, C, X, G, B, |Z|, and |Y|


.09
 Z m * 10 7
A%   0.025    0.025 

Zm



 *  0V.2  0.8 * VV
fs
 
s

s
Vs  12 
4

F
300  
 0.7  m5 
  * K t
*

F
10
m
 
 
Vs = Test voltage in voltage mode, I * Zm in current mode*
Zm = Impedance of DUT
Fm = Test frequency
Kt = 1 for 18o to 28oC, 2 for 8o to 38oC, and for 4 for 5o to 45oC
57
7600 Plus LCR Meter
151053 A4
* For I * Zm > 3, accuracy is not specified
VFS = 5.0 for 1.000V  Vs  5.000V
1.0 for 0.100V  Vs  1.000V
0.1 for 0.020V  Vs  0.100V
For Zm  4* ZRANGE multiply A% by 2
For Zm  16* ZRANGE multiply A% by 4
For Zm  64* ZRANGE multiply A% by 8
In Voltage Mode
In Current Mode
where 100k for Zm  25k
ZRANGE =
400 for i < 2.5mA
6k for 1.6k  Zm  25k
25 for i > 2.5mA
6k for Zm  25k and Fm  25kHz
400 for 100  Zm  1.6k
400 for Zm  1.6k and Fm  250kHz
25 for Zm  100
NOTE: Calculated Rs accuracy applies only when device under test is primarily reactive
Calculated ESR accuracy applies only when device under test is primarily capacitive
The unit is unspecified for Fm  1.0 MHz and Vs  0.5V and for Fm  500 kHz and
Vs  1.0V
D Accuracy
Q Accuracy
 A% D  
Fm 

  * 1 

5*104 
 100 50  
 Accuracy

A%  180 
*

20   
D = DF of unknown

A% 
A%  A% 1 
A

  * Q  Q2  n 
100  100 50 
100 500 
ESR Accuracy
 A% 

 * Zm
 100 
Q = Q of unknown
A% = calculated primary accuracy for all cases
1 MHz Special Case Accuracy
(1 MHz, C = 100pF to 1000 pF, Zm 158 to 1.6k, D or Q < 0.01, voltage mode, Vs 
1V)
Fast Mode Accuracy
58
7600 Plus LCR Meter
151053 A4
 An 


.2 Vs 2    2 * VFS  Vs  

A%   
* .067 * 1 

   An .05 * K t
 * 
VFS
Vs
4  


 0.05 

An = nominal accuracy 0.5.
Medium Mode Accuracy
2

 A 

.2 V    2 *VFS  Vs  
   An  .05 * K t
A%    n *  .067 *  0.8   s   * 

Vs
4   
VFS



 0.05 
An = nominal accuracy 0.25.
Slow Mode Accuracy
2

 A 

.2 Vs    2 *VFS  Vs  
n


 *



* .067 *  0.55  
A%   
A
.
05


 * Kt
n

Vs
4   
VFS

 0.05 


An = nominal accuracy 0.05.
NOTE:
Accuracy given by the equations is the measurement accuracy relative to calibration
standards. Total accuracy equals the relative measurement accuracy plus the calibration
uncertainty of the calibration standards.
2.9.7 Open / Short
The zeroing process automatically measures stray parameters and retains the data, which
is used to correct measurements so that results represent parameters of the DUT alone
without test lead or fixture capacitance. Measurement accuracy is specified at the end of
the IET Labs one meter cable (7000-01). Open and short circuit zeroing should be done
at the end of this cable. In order to maintain instrument accuracy with other cable lengths
the instrument should be re calibrated using the IET Labs 7000-09 Calibration Kit and
the alternate cable. Zeroing is recommended at the start of each work day or more often
if leads, fixture or test configuration to the DUT is changed. It is not necessary to rezero if the test frequency is changed. It is important to note, that anytime the
instrument is zeroed it is done at a test voltage of 1 volt and frequencies of 10, 50,
100Hz, 1, 5, 10, 25, 50, 100, 250, 500, 750kHz, 1, 1.25, 1.5, 1.75 and 2MHz. Once
Open/Short is selected in the menu and Enter key pressed the operator is prompted by
instructions on the display for short or open zeroing as shown in Figure 47 below. When
zeroing, Contact Check should be OFF, # to Average to 1 and Median OFF.
When the instrument measurement accuracy is selected for SLOW the unit will perform
its Open/Short in this mode. When the instrument accuracy is selected for MEDIUM or
FAST the unit will perform its Open/Short in the Medium mode. The Open/Short
performed in the Slow mode is necessary only for measurements with extreme accuracy
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requirements at very high or low impedance. Open/Short takes about 5 minutes in the
Medium mode versus about 15 minutes in the Slow mode.
When Quick Open & Short is selected the zeroing process is performed as prompted on
the display, in much less time and only at the frequency currently selected on the
instrument. It is important to note that the quick open and short data is no longer valid if
frequency is changed, if sweep or sequence is selected or instrument powered down.
Short
Connect an Open or a
Open
Short to the instrument
Press the function key
for the connection desired.
HIT MENU TO RETURN TO MAIN MENU
Quick
Open &
Short
Figure 47 Open / Short
2.9.8 Lock Out
LOCKOUT WITH
SETUP RECALL
SELECT THE LOCK OUT TYPE
HIT <CNCL> TO EXIT
LOCKOUT
ONLY
Figure 48 Lockout
Allows user to turn keypad lock feature on or off. There are two choices that can be
selected, lockout only and lockout with setup recall. In both modes only the START,
STOP and MENU on the instrument front panel are active, all other keys disabled. The
difference is that in lockout with setup recall the menu key also allows setups to be
recalled from instrument memory.
When either is selected the operator must enter a password number up to 8 characters.
CAUTION
For security reasons, the password is not displayed
when it is entered, so the password should be keyed in
distinctly and remembered. Failure to remember an
entered password requires the factory override, 760001
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ENTER PASSWORD
.
(8 CHARACTERS MAXIMUM, default 760001)
********
Once the password is entered and entered again for verification, testing can begin by
pressing START or the password cleared or changed by selecting MENU.
HIT <MENU> KEY TO ENTER PASSWORD
AND TO RETURN TO THE MENU
OR
HIT THE <START> KEY TO
START A MEASUREMENT
Once activated, only the START, STOP and MENU on the instrument front panel are
active, all other keys are disabled. To turn the lockout feature off and reactivate menus
select MENU (select Exit Lockout in Lockout with Setup Recall mode) and enter the
previous password from the keypad, the instrument will again function as normal.
If Recall Setups is chosen in the Lockout with Setup Recall mode, the instrument
functions as described in paragraph 2.6.5.2 under Recall Setup.
2.9.9 Calibration
Refer to Calibration on page 96. INSTRUMENT CALIBRATION SHOULD ONLY
BE PERFORMED BY QUALIFIED SERVICE PERSONNEL.
2.9.10 Set Time/Date
Wed Aug 19 10:30:10 2008
T
TO CHANGE TIME PRESS T KEY
TO CHANGE TIME PRESS D KEY
TO RETURN PRESS <MENU>
D
Figure 49 Set Time / Date
Allows resetting of time and date into unit memory. This is used as the basis for the
elapsed time counter and stored calibration date.
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T (time) is entered in
HOURS
(up to 2 digits, 0 through 23)
MINUTES
(up to 2 digits, 0 through 59)
SECONDS
(up to 2 digits, 0 through 59)
MONTHS
(up to 2 digits, 1 through 12)
DAYS
(up to 2 digits, 1 through 31)
YEARS
(4 digits, 1992 through 2037)
D (date) is entered in
2.9.11 Usage/Cal Date
QuadTech 7600 Plus Version 1.17
THE TOTAL OPERATING TIME FOR
THIS INSTRUMENT IS
1205.50 hours
THIS INSTRUMENT WAS CALIBRATED ON
10/15/2008
AT 11:25:10
HIT <MENU> KEY TO CONTINUE
cal
data
Figure 50 Usage / Cal Date
When selected, indicates the total elapsed time in hours that the unit has been powered up
and the date of last calibration. The elapsed time is from the moment of initial use and
may show some time when shipped from the factory. The calibration date is retained in
instrument memory unit the unit is re calibrated and then it is updated. When cal data is
selected, the calibrated values are shown as entered from the Report of Calibration
provided with the 7000-09 Calibration Kit previously used.
2.9.12 Set Contrast
HIT ARROW KEYS TO
CHANGE THE DISPLAY CONTRAST
HIT <ENTER> TO ACCEPT
THE CONTRAST SETTING
Figure 51 Set Contrast
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Allows adjustment of contrast on the LCD display. Use Up arrow to increase contrast or
Down arrow to decrease. When the instrument is powered up it returns to the last set
contrast, not some nominal level.
2.9.13 Self Test
When selected, runs a group of internal self tests to verify that calibration and open/short
data are not corrupt.
2.9.14 LCD Backlite
Allows the backlite on the LCD display to be Save or On. When set to Save the backlite
turns off automatically if no keypad has been hit for 5 minutes and turns back on with the
touch of START, MENU or ENTER keys. When set to On the backlite is constantly on.
The Save mode will prolong the life of the display.
2.10 Input/Output Interface
The 7600 Plus comes standard with an automatic component handler I/O interface port
available through a 36 pin Centronics type connector located on the rear panel of the
instrument. This port outputs signals to indicate measurement in process, measurement
completed, and bin sorting judgments. The Handler Interface also has inputs for an
external trigger signal and a safety interlock signal. All output lines are negative true,
optically isolated, open collector. Pull-up resistors to allow operation from +5V to +24V
logic must be implemented externally. Inputs are optically isolated, and can be current
driven from either positive or negative true logic. Current limiting resistors to allow
operation from +5V to +24V logic must be implemented externally.
Refer to Table 1 for signal names, pin numbers and functions as necessary for cable
connections.
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Table 1 I/O Interface Connections
Signal Name
Pin Number
Function
-Bin1
1
Bin Sorting Results (Bin1-Bin10)
-Bin2
19
All signals active low, open collector
-Bin3
2
-Bin4
20
-Bin5
3
-Bin6
21
-Bin7
4
-Bin8
22
-Bin9
6
-Bin10
24
-Bin11
7
Primary parameter pass, secondary fail low
-Bin12
25
Primary parameter pass, secondary fail high
-Bin13
8
Primary parameter fail, secondary pass
-Bin14
26
Primary parameter fail, secondary fail
-Bin15
9
No Contact
-Bin16
27
Unused
-EOT
data valid.
29
End of Test, test completed; bin and measurement
-BUSY
30
Measurement/comparison in progress
TRIG+
14
Trigger high input
TRIG-
16
Trigger low input
START+
34
Isolated Trigger high input
START-
35
Isolated Trigger low input source
GND
11, 15, 33
System common
IGND
5, 10, 23, 28
Isolated common
+5V
12, 32
System +5V through 100 
INT+
13
Interlock high input from external source
HTC
31
Handler timing control
18
36
1
19
Pin Configuration (Viewed from Rear Panel)
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CAUTION
Do not apply an external source in excess of 5 volts with jumpers JP2401, JP2402, or
JP2403 in place, otherwise the instrument can be damaged. The instrument is
shipped with these jumpers in place and must be removed for optical isolation.
These jumpers are discussed below.
The operation of START and TRIG circuits is identical. Both inputs are active low, for
optical isolation they require a positive +5 to +24V external source and current limiting
resistor to operate. START is always optically isolated. TRIG can be converted to a
isolated active low input by removing jumper JP2402 on the I/O PCB. Both signals are
open collector OR'ed on the I/O PCB; current flowing through the isolator input on either
signal causes a single Start line to be pulled low.
The INTerlock signal can be optically isolated, and also requires a positive +5 to +24V
external source and current limiting resistor to operate. This signal can be converted to a
isolated active low input by removing jumper JP2403 on the I/O PCB. Current flowing
through the isolator input causes the internal Interlock line to be driven low.
All bin and control outputs can be active low optically isolated open - collector drivers
that pull each signal line to IGND (isolated common) when asserted. All outputs require
a positive +5 to +24V external source (referenced to IGND) and pull-up resistor to
operate as fully isolated signals. IGND can be isolated from system GND by removing
jumper JP2401 on the I/O PCB. With jumper JP2401 in place, optical isolation is
defeated, which allows the outputs to be pulled up to the system +5V with external
resistors.
10 us min
Active
START
EOT
(pin 31 floating)
EOT
(pin 31 grounded)
BUSY
Bin Data
Previous Data Valid
Data Valid
2nd Test
10 us min
End of Measurement
Figure 52 I/O Interface Timing
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Test Initiation

A test is initiated by activating either the START± or TRIG± inputs.

The BUSY line is asserted low to indicate that a measurement is in progress.

The EOT line is de-activated (asserted high) to indicate that the end of the test
had not been reached

Binning data from the previous test is still valid.
During a Test

The START± or TRIG± inputs are released and return to their inactive

The BUSY line is held low to indicate the 7600 Plus is making a measurement.

The EOT line is held high (inactive) until the 7600 Plus is done making a
measurement and bin data is valid.
state.
End of Test

The BUSY line is returned to high impedance (de-activated) to indicate that the
7600 Plus is done making a measurement and to signal the automatic component
handler to advance the DUT to the binning station and insert the next DUT.

Simultaneously, the EOT line is asserted low to indicate that the test is completed,
bin data lines and measurement data are valid and can be read from the IEEE or
RS-232 ports. Data must be valid a minimum of 10us before the trailing edge of
BUSY and EOT.

All data for the current test is valid, and will remain valid until the end of the next
test. This includes comparator bins 1-10, primary and secondary parameter bins
11-15, and analog measurement data.
Electrical Characteristics
Inputs: START±, TRIG±
Condition
Input Current
Input Voltage
5 - 50 mA
5 - 24V
5 - 50 mA
5 - 24V
Active High
Signal+ current driven, Signal- @ IGND
Active Low
Signal-current driven, Signal+ @ V+(ext)
Outputs:-Bin1 -Bin16, -EOT, -BUSY
Condition
Sink Current
Output Voltage
Low
High
Binning signals
200 mA max (150mW)
< 0.5V
5 – 40V
Control signals
200 mA max (150mW)
< 0.5V
5 – 40V
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151053 A4
Figure 53 I/O Interface Isolation
The outputs are optically isolated for added interfacing flexibility and to increase
reliability by reducing noise pickup and ground loop interference. The optocouplers use
open collectors, and can sink up to 200mA of current provided by an external source at
up to 40V. No provisions for pull-up resistors are provided on - board. The isolated
ground return can be floated, or connected to the 7600 Plus system ground for use with
isolated handlers. The isolators are driven by inverting high current buffers.
All inputs are also optically isolated. Both anode and cathode of the input opto-isolators
are available in the handler interface connector. Active high inputs can be achieved by
grounding the cathode ( "-" signal ) and driving the anode ( "+" signal ), while connecting
the anode to the external supply and sinking current through the cathode will result in
active low drive. No provisions for current limiting resistors are provided on - board.
All inputs are reverse bias protected; max. 5V reverse voltage, 50mA (60mW).
2.11 Parallel Interface
The 7600 Plus comes standard with a parallel printer port available through a connector
(25 pin) on the rear panel of the instrument. This is a standard PC compatible interface
for connection to a printer. Refer to Table 2 for signal names, pin numbers as necessary
for cable connections.
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Table 2 Parallel Interface Connections
Signal Name
Pin Number
Function
Outputs:
-STROBE
1
Indicates that data is ready to read
0
2
Data bit 1
D1
3
Data bit 2
D2
4
Data bit 3
D3
5
Data bit 4
D4
6
Data bit 5
D5
7
Data bit 6
D6
8
Data bit 7
D7
9
Data bit 8
-AUTOFD
14
Auto paper feed
-INIT
16
Initializes printer
-SLCT IN
17
Selects printer
GROUND
18 - 25
Signal ground
Inputs:
-ACK
10
Indicates that data has been received and printer is
ready to accept more data
BUSY
11
Indicates that printer can not receive data
PE
12
Indicates that printer is out of paper
SLCT
13
Indicates that printer is ready to receive data
-ERROR
15
Indicates printer error
13
25
1
14
Pin Configuration (Viewed from Rear Panel)
2.12 IEEE-488.2 Interface Optional
The 7600 Plus has an optional IEEE-488 interface with connection through a connector
(24 pin) on the rear panel. This interface can be used to connect to a system containing a
number of instruments and a controller in which each meets IEEE Standard 488.2
(Standard Digital Interface for Programmable Instrumentation). Refer to Table 3 for the
command set.
The following functions have been implemented. Refer to the standard for an
explanation of the function subsets, represented by the identifications below.
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151053 A4
SH1
Source Handshake
PP1
Parallel Poll
AH1
Acceptor Handshake
DC1
Device Clear
T5
Talker
DT1
Device Trigger
L3
Listener
C0
Controller
SR1
RL1
Service Request
Remote Local
E2
Electrical Interface
Table 3 IEEE & RS-232 Commands
Command
Function
Parameter(s)
FREQuency
Set the frequency from 10 to 2000000 Hz
0000000.00
PPARameter
Set the primary parameter
A(auto) CS CP LS
LP RP RS DF Q Z Y
P(phase angle) ESR
GP XS BP
SPARameter
Set the secondary parameter
N(none) CS CP LS
LP RP RS DF Q Z Y
P(phase angle) ESR
GP XS BP
ACTYpe
Set the AC test signal type to
V I
CONFigure:
This command should be set prior to setting the ACValue.
ACValue
Set the AC signal to value
0.0
BIAS
Set the bias to
INT EXT or OFF
RANGe
Set the range
AUTO or HOLD or
#(1-59)
MACcuracy
Set the measurement accuracy
SLOw MEDium
FASt
TDELay
Set the measurement delay
#####
AVERage
Set # to average
###
MEDian
Set the median function to ON or OFF
ON OFF
DISTortion
Set distortion detection to ON or OFF
ON OFF
CCHeck
Set the contact check to ON or OFF
ON OFF
DISPlay type
Set display type to
M (Measured
Parameter)
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D (Deviation from
Nominal)
% (% Deviation from
Nominal)
B (Bin Number)
S (Bin Summary)
P (Pass/Fail)
N (No Display)
TRIGger
Set the trigger to
INTernal EXTernal
NOMinal
Set the nominal value
floating point #
(for deviation or % deviation)
CONFigure:
BINNing:
bin#
ABS*
Set the low & high limit for the bin
low high (floating
point #'s)
TOL
Set the % below, % above and nominal
value
% below % above
nominal (3 floating
point #'s w/space
between)
SECondary
Set the secondary low & high limit
low high (floating
point #'s)
TRESet
Reset the bin totals to zero
SUMMary?
Retrieve the bin summary data
FRESult
Set the result format to
SCIentific
ENGineering
HANDler (state)
Turn handler port OFF or ON
ON OFF
RPRint
Turn print results ON or OFF
ON OFF
RUSBppy:
Results to USB
DUPLicate
Save results as duplicate filename on flash drive
xxxxxxxx
NEW
Save results as new filename on flash drive
xxxxxxxx
APPend
Append results to existing filename
xxxxxxxx
CLOSe
Close results of filename
xxxxxxxx
SWEep:
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7600 Plus LCR Meter
PARameter
151053 A4
The parameter to sweep
F (frequency)
V (voltage)
I (current)
BEGin
The beginning value
floating point number
END
The ending value
floating point number
STEP
The step to increment during the sweep
10 25 50 100 200
RDISplay
The result display for the sweep
T (table) P (plot)
SWEep
Set the sweep function to ON or OFF
ON OFF
VALid?
Is filename valid to save to battery backed up RAM?
* Example CONF: BINN: BIN1: ABS 100 300
CONFigure:
SAVe:
DUPLicate
xxxxxxxx
Save setup as duplicate filename in battery backed up RAM
NEW
Save setup as new filename in battery backed up RAM
RECall filename
Recall setup filename from battery backed up RAM
FVALid?
Is filename valid to save to flash drive?
xxxxxxxx
FSAVe:
DUPLicate
Save setup as duplicate filename on flash drive
NEW
Save setup as new filename on flash drive
xxxxxxxx
xxxxxxxx
FRECall filename Recall setup filename from flash drive
xxxxxxxx
RVALid?
Is results filename valid?
xxxxxxxx
SEQuence
Set the sequence function to ON or OFF
ON OFF
TEST
Enable or Disable a test
test #(1-6) and
SEQuence:
ENAble DISable
FREQuency
Set the frequency from 10 to 2000000 HZ
PPARameter Set the primary parameter
test # and ######.##
test # and A(auto) RS
RP LS LP CS CP DF
Q Z Y P(phase angle)
ESR GP XS BP
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SPARameter Set the secondary parameter
test # and N(none)
RS RP LS LP CS CP
DF Q Z Y
P(phase angle)ESR
GP XS BP
ACTYpe
Set the AC test signal type to
test # and V I
(This command should be set prior to setting the ACValue)
ACValue
Set the AC signal to value
test # and 0.0
BIAS
Set the bias to
test # and INT EXT
or OFF
RANGe
Set the range
test # and ON OFF
TDELay
Set the measurement delay
test # and ####
STOP
Stop on fail
test # and ON OFF
NOMinals
Set primary & secondary nominal values
primary secondary
(floating point #'s)
MEAsure
Perform the Correction Measurement and
LOAd correction:
set Load Correction to On
ON
Set Load Correction to ON (valid only if a
Correction Measurement has previously been made
OFF
Set Load Correction to Off
SYSTem:
TIME
Set the time to hours, minutes
hh:mm
DATE
Set the date to month, day, year
mm/dd/yyyy
LOCKout state
Set the front panel lockout off or on
ON OFF
ELAPsed?
Query the elapsed time the machine has run
DCALibration?
Query the calibration date
BLCD
Turn lcd backlite ON or set to screen save
ON SAVE
Caution: Setting the remote LOCKout state with certain screens displayed on
the unit can prevent one from entering or exiting lockout.
CALibrate:
72
DATA?
Returns the calibration data to the user
QUIckos
Perform quick open calibration
7600 Plus LCR Meter
151053 A4
IEEE wait for SRQ OPC to indicate continue
Send
Any command if desired to implement
Send
Fetch? This will continue calibration
Receive
Connect the Open Circuit. Ensure that the
open is connected to the instrument
Send
CONTINUE
Wait for SRQ OPC (operation complete, IEEE only)
Perform quick short calibration
Send
Any command if desired to implement
Send
Fetch? This will continue calibration
Receive
Connect the Short Circuit. Ensure that the
short is connected to the instrument
Send
CONTINUE
Receive
Complete (for RS232 only)
Wait for SRQ OPC (operation complete, IEEE only)
SHORt
Perform short circuit calibration
The procedure for performing a remote short is as follows:
IEEE wait for SRQ OPC to indicate continue
Send
Any command if desired to implement
Send
Fetch? This will continue calibration
Receive
Connect the Short Circuit. Ensure that the
short is connected to the instrument
Send
CONTINUE
Receive
Complete (for RS232 only)
Wait for SRQ OPC (operation complete, IEEE only)
OPEN
Perform open circuit calibration
The procedure for performing a remote open is as follows:
IEEE wait for SRQ OPC to indicate continue
Send
Any command if desired to implement
Send
Fetch? This will continue calibration
Receive
Connect the Open Circuit. Ensure that the
open is connected to the instrument
Send
CONTINUE
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Receive
Complete (for RS232 only)
Wait for SRQ OPC (operation complete, IEEE only)
FULL
Perform full calibration
The procedure for performing full calibration is as follows:
IEEE wait for SRQ OPC to indicate continue
Send
Any command if desired to implement
Send
Fetch? This will continue calibration
Receive
Connect the 374  Standard. Ensure that
the standard is connected to the instrument
Send
CONTINUE
IEEE wait for SRQ OPC to indicate gain cal is done
Send
Any command if desired to implement
Send
Fetch? This will continue calibration
Receive
Connect the open circuit. Ensure that
the open is connected to the instrument
Send
CONTINUE
IEEE wait for SRQ OPC to indicate open circuit cal is done
Send
Any command if desired to implement
Send
Fetch? This will continue calibration
Receive
Connect the short circuit. Ensure that
the standard is connected to the instrument
Send
CONTINUE
IEEE wait for SRQ OPC to indicate short circuit cal is done
Send
Any command if desired to implement
Send
Fetch? This will continue calibration for the
Receive
Connect the standard. Ensure that
the standard is connected to the instrument
Send
CONTINUE
Send
Any command if desired to implement
Send
Fetch? This will continue calibration
Receive
Get prompt for Rnom and Qnom values at
1 kHz
next 4 standards
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IEEE wait for SRQ OPC to indicate current standard cal is done
Send
Any command if desired to implement
Send
Fetch?
Receive
Get prompt for Rnom and Qnom values at
1 MHz or 50 kHz
IEEE wait for SRQ OPC to indicate range cal is done
Send
Any command if desired to implement
Send
Fetch?
after last standard
IEEE wait for SRQ OPC
RS232 wait for Complete
MEASure
Triggers a measurement of the selected type. If sequence or sweep is enabled this
command will trigger those type of measurements also. The result type is set by the
display type parameter.
FETCh?
Fetches the most recent measurement results. The character sequence formats are as
follows:
Normal Measurements:
<primary result name> <tab> <primary result> <tab> <units> <secondary result name>
<secondary result> <tab> <units> <tab> <bin or tab> <tab> <#> <tab> <pass string or
fail string or tab> <tab> <retest or tab> terminated by a linefeed.
The secondary parameter will be blank when the parameter is set to NONE.
Sweep Measurement:
If sweep is enabled, fetch will give all of the results based on the number of steps
selected with the normal measurement format.
FETCh?
Sequence Measurement:
If sequence is enabled, results will be sent for each test enabled.
1st line: <pass/fail bin> <tab> <#>,
additional lines for tests enabled: <test> <tab> <#> <tab> <primary result> <tab>
<units> <tab> <secondary results> <tab> <units> <tab> <fail or tab>, .last line for tests
enabled: <test> <tab> <#> <tab> <primary result> <tab> <units> <tab> <secondary
results> <tab> <units> <tab> <fail or tab> terminated by a linefeed.
Bin Summary Measurement:
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Bins 1 - 10
<bin> <tab> <#> <tab> <low limit> <tab> <# or tab> <tab> <high limit> <tab> <# or
tab> <tab> <total> <tab> <#> terminated by a linefeed.
Bins 11 - 15
<bin> <tab> <#> <tab> <bin description> <tab> <total> <tab> <#> terminated by a
linefeed.
Last Line
<totals:> <tab> <pass> <tab> <#> <tab> <fail> <tab> <#> <tab> <#> <tab> <total>
terminated by a linefeed.
LOADFEtch?
Returns load correction status Valid, measured primary & secondary values
or
Invalid
*IDN?
Returns instrument identification "IET Labs,7600Plus,xx...xx,software version".
*ESR?
x denotes serial number up to 10 digits
Returns the read of the event status register.
*STB?
Returns the read of the status byte register.
*ESE?
Returns the read of the event status enable register.
*SRE?
Returns the read of the service request enable register.
*ESE
Set the event status enable register value
*SRE
Set the service request enable register value
*RST
Reset the buffer
*TST?
Self test query
*CLS
Clear standard event status register
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Note: Remote command can start with or without * symbol for compatibility.
2.13 Formats
IEEE 488.2 enables remote programming of all instrument functions, measurement
conditions and comparator settings etc. Outputs include measurement conditions,
open/short corrections, and measured values.
Data Formats
Data will be transmitted in ASCII NR3 format per IEEE488.2 sec. 8.7.4 and reproduced
below. Note that there is always precisely one digit before the decimal point, and
precisely three digits in the exponent.
Multiple results
For the case where a measurement produces multiple results (e.g. MEASure Cs, and DF),
the individual numbers will be separated by commas per IEEE488.2 para. 8.4.2.2.
Sequences of Test (Sequence Mode) will be treated as a single Message Unit, with results
separated by commas. If a particular test has “None” selected as a secondary parameter,
no place will be reserved for the null result. As an example, a sequence of three tests
asking for C/D, ESR, and Z/ would appear as follows:
<data>,<data>,<data>,<data>,<data><NL>
All response messages will be terminated by the NL character together with the EOI line
asserted.
Status Byte Register
Decimal
Bit
Value
Use
7
128
None
6
64
SRQ, SPOL Resets
5
32
Summary of Standard Event
Status Register*
4
16
Message Available
3
8
None
2
4
None
1
2
None
0
1
None
*The Status Byte Regester is readable via the standard STB? as defined in para. 11.2.2.2
of the IEEE spec. The 7600 Plus will also implement an SRE register to enable each bit
of the Status Byte Register per para 11.3.2 of the IEEE spec. This register shall be
readable by a SRE? command and writeable by a SRE <#> command.
Standard Event Status Register
Decimal
Bit
Value
7
128
6
64
5
32
4
16
3
8
2
4
Use
Power Up Since Last Query
None
Command Error (Syntax)
Execution Error (Over Range, etc.)
No Contact
Query Error
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1
2
None
0
1
Operation Complete
This register is read by executing an “ESR?” command, page 76 (except no *). Note that
this is a destructive read. Reading the register clears it. Each bit of the Event register
must be enabled in order to cause the ESB bit of the Status Register to be set. This
enabling is done in the Standard Event Status Enable Register by issuing an ESE
command.
2.13.1 Sample Program for National Instruments GPIB card
260 '*SAMPLE 7600 Plus BASIC PROGRAM FOR NATIONAL INSTRUMENTS
IEEE **
' Merge National DECL.BAS here
270 ADAP$="GPIB0" : DEV4$="Dev4": R$ = SPACE$(60)
280 CALL IBFIND (DEV4$,DEV4%)
290 CLS '***** SET CONDITIONS, MEASURE, AND DISPLAY DATA
************
300 SET$="CONF:REC DEFAULT"
: CALL IBWRT (DEV4%,SET$)
310 SET$="CONF:FREQ 1000.00" : CALL IBWRT (DEV4%,SET$)
320 SET$="CONF:PPAR CS"
: CALL IBWRT (DEV4%,SET$)
330 SET$="CONF:SPAR DF"
: CALL IBWRT (DEV4%,SET$)
340 SET$="CONF:MAC ENH"
: CALL IBWRT (DEV4%,SET$)
350 SET$="CONF:NOM 0"
: CALL IBWRT (DEV4%,SET$)
360 SET$="CONF:DISP M"
: CALL IBWRT (DEV4%,SET$)
370 SET$="MEAS:"
380
: CALL IBWRT (DEV4%,SET$)
FOR I = 1 TO 5000 : NEXT I
390 SET$="FETC?"
: CALL IBWRT (DEV4%,SET$)
400 CALL IBRD (DEV4%,R$) : PRINT R$
410 CALL IBLOC (DEV4%)
420 END
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2.13.2 RS232 Interface
The 7600 Plus comes standard with an RS232 serial port interface, available through a
connector (9 pin) on the rear panel of the instrument, for connecting to a PC. The RS232
standard defines electrical specifications for the transmission of bit serial information.
The use of the RS232 port requires five lines, receive data, transmit data, data terminal
ready, data set ready and signal ground. With some controllers additional signals maybe
required and are listed in Table 4 below. Refer to Figure 54 for null modem cable
configuration to the standard db9 or db25 connector. Refer to Table 3 for the command
set.
Table 4 RS232 Interface Connections
ignal Name
Pin Number
Function
Inputs:
DCD
1
Data Carrier Detect
DSR
6
Data Set Ready
RXD
2
Receive Data
CTS
8
Clear to Send
RI
9
Ring Indicator
Outputs:
RTS
7
Request to Send
TXD
3
Transmit Data
DTR
4
Data Terminal Ready
GND
5
Signal Ground
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7600 Plus
Controller
Pin #
Function
Pin #
Function
2
Receive data
Connect
3
Transmit data
3
Transmit data
to
2
Receive data
4
Data terminal ready
6
Data set ready
5
Signal ground
5
Signal ground
6
Data set ready
4
Data terminal ready
db9 to db9 Cable Configuration
7600 Plus
Pin #
Function
2
Receive data
3
Transmit data
4
Controller
Pin #
Function
Connect
2
Transmit data
to
3
Receive data
Data terminal ready
6
Data set ready
5
Signal ground
7
Signal ground
6
Data set ready
20
Data terminal ready
db9 to db25 Cable Configuration
Figure 54 RS-232 Cable Configurations
2.13.3 Results to Printer
The 7600 Plus can be setup to output to an RS-232 or IEEE printer.
RS-232
RS-232 must be selected on I/O Menus and format set IEEE must also
be selected for Talk mode and Disable state.
IEEE
IEEE must be selected on I/O Menus and set for Address, Talk mode
and Enable state.
2.14 Operation with Accessories
A wide selection of accessories such as test leads, cables and fixtures are available from
IET Labs to enhance the operation of the 7600 Plus Precision LCR Meter.
NOTE:
Instrument accuracy can be reduced from nominal specifications when using some 7000
accessory fixtures and cables. Best accuracy requires geometric consistency between that utilized
during open/short zeroing and that utilized on fixtures and cables during the actual measurement
process. This consistency may be especially difficult to achieve when using unshielded Kelvin
clip and tweezer type connections.
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2.14.1 Rack Mount Kit (7000-00)
The 7000-00 Rack Mount Kit is used to install the 7600 Plus in a rack mount
configuration. The main components of the kit include front handles, front angle
brackets, rear vertical trim pieces and rear support brackets. Assembly instructions (IET
Labs Form # 150077) are provided with the kit.
2.14.2 BNC Cable Set, 1 Meter (1689-9602), 2 Meter (1689-9602-02)
The 1689-9602 and 1689-9602-02 are BNC to BNC cable sets used for connecting
fixtures, component handlers or other measurement devices to the measurement terminals
of the 7600 Plus. The only difference between the two is that the 1689-9602 cable is 1
meter in length and the 1689-9602-02 is 2 meters in length.
Rd/Wh
Rd/Wh
PH
PH
Rd
Rd
IH
IH
Bk/Wh
Bk/Wh
PL
PL
Bk
Bk
IL
IL
Figure 55 BNC Cable Sets
Connection to 7600 Plus:
Connect to 7600 Plus
Cable Marking/Color
Connection to DUT
PH (potential, high)
PH (Red/white)
Positive (+) terminal of DUT
IH (current, high)
IH (Red)
Positive (+) terminal of DUT
PL (potential, low
PL (Black/white)
Negative (-) terminal of DUT
IL (current , low)
IL (Black)
Negative (-) terminal of DUT
Note: H and L denote polarity of AC test signal at 7600 Plus measurement terminals
as well as the + and - polarity of DC bias voltage when applied.
2.14.3 Kelvin Clip Leads (1700-03)
The 1700-03 Kelvin Clip Leads provide a means for easily making four-terminal
connections to passive sensors and components when they are tested by the 7600 Plus.
This cable is especially useful for testing low-impedance devices that have large or nonstandard terminations, devices such as electrolytic capacitors and inductors.
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Rd/Wh
Rd/Wh
PH
PH
Rd
Rd
IH
IH
Bk/Wh
Bk/Wh
PL
PL
Bk
Bk
IL
IL
+
+ and - denote polarity
of DC bias voltage
Figure 56 Kelvin Clip Leads
For this accessory an additional accuracy (for parameters listed) must be added to the
standard instrument accuracy as defined by AutoAcc.
C: ± 1.5 pF
R: ± 10 m
L: ± 100 nH
Q: for R > 100 , ± 9 * Freq * R * 10 -12 ppm
for R < 100 , ± (R/Freq) * 10 -6 ppm
Measurement accuracy is very sensitive to connection geometry. The same connection
geometry must be used for open/short compensation as for connection to the device under
test.
Connection to 7600 Plus:
Connection to the 7600 Plus is made through four shielded cables with BNC connectors
that mate directly with the measurement terminals of the 7600 Plus. The cables are color
coded to facilitate proper connections as detailed below.
Connect to 7600 Plus
Cable Marking/Color
PH (potential, high)
PH (Red/white)
Positive (+) terminal of DUT
IH (current, high)
IH (Red)
Positive (+) terminal of DUT
PL (potential, low
PL (Black/white)
Negative (-) terminal of DUT
IL (current, low)
IL (Black)
Negative (-) terminal of DUT
Connection to DUT
NOTE:
H and L denote polarity of AC test signal at 7600 Plus measurement terminals as well as
the + and - polarity of DC bias voltage when applied
Open/Short Zeroing:
When these Kelvin Test Leads are used, an open/short-circuit "zeroing" procedure should
be done (page 10) to correct for residual resistance and inductance. The following
diagram shows how to connect the clips for the short-circuit "zero."
82
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7600 Plus LCR Meter
White
151053 A4
Black
Red
White
Figure 57 Kelvin Test Leads Open/Short Zeroing
2.14.4 Alligator Clip Leads (7000-04)
The 7000-04 Alligator Clip Leads is generally used to connect to devices that are multiterminal, physically large or otherwise unsuited for one of the remote test fixtures. The
lead set is consists of a BNC to BNC cable, four banana plug adapters and four alligator
clips. One of the banana plug adapters is supplied with a pigtail for connecting a "guard"
if necessary.
Rd/Wh
Rd/Wh
PH
PH
Rd
Rd
IH
IH
Bk/Wh
Bk/Wh
PL
PL
Bk
Bk
IL
IL
Figure 58 Alligator Clip Leads
For this accessory an additional accuracy (for parameters listed) must be added to the
standard instrument accuracy as defined by AutoAcc.
C: ± 1.0 pF
R: ± (10 m + R/5 * 106)
Q: ± 50 ppm
for R > 100 , ± 4 * Freq * R * 10 -13 ppm
Measurement accuracy is very sensitive to connection geometry. The same connection
geometry must be used for open/short compensation as for connection to the device under
test.
Connection to 7600 Plus:
Connect to 7600 Plus
Cable Marking/Color
Connection to DUT
PH (potential, high)
PH (Red/white)
Positive (+) terminal of DUT
IH (current, high)
IH (Red)
Positive (+) terminal of DUT
PL (potential, low
PL (Black/white)
Negative (-) terminal of DUT
IL (current, low)
IL (Black)
Negative (-) terminal of DUT
Guard of DUT
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NOTE:
H and L denote polarity of AC test signal at 7600 Plus measurement terminals as well as the + and polarity of DC bias voltage when applied
2.14.5 Chip Component Tweezers (7000-05)
The 7000-05 Chip Component Tweezers can handle small unleaded "chips" or SMDs
(surface mounted devices), passive sensors, and components for testing on the 7600 Plus.
A four-terminal Kelvin connection extends to the tip of the tweezers where the
measurement becomes two-terminal, therefore series impedance of the connecting cables
and internal tweezer connections do not affect the measurement. The small amounts of
residual-tip resistance and inductance can be automatically corrected by using the 7600
Plus shorting function with the tips pressed together. Guard shields between the tweezer
blades minimize capacitance between them. A correction for this small capacitance can
be made using the 7600 Plus open circuit test with the tips held at a spacing equal to that
of the component's contact spacing.
Bk
or labeled
LD
IL
or labeled
LS
Bk/Wh
+
PL
Rd
or labeled
HD
IH
Rd/Wh
PH
or labeled
HS
Figure 59 Chip Component Tweezers
For this accessory an additional accuracy (for parameters listed) must be added to the
standard instrument accuracy as defined by AutoAcc.
C: ± 1.5 pF
R: ± 10 m
L: ± 100 nH
Q: for R > 100 , ± 9 * Freq * R * 10 -12 ppm
for R < 100 , ± (R/Freq) * 10 -6 ppm
Measurement accuracy is very sensitive to connection geometry. The same connection
geometry must be used for open/short compensation as for connection to the device under
test.
Connection to 7600 Plus:
Connect to 7600 Plus
Cable Marking
Connection to DUT
PH (potential, high)
PH (Rd/Wh) or HS
+ to positive (+) terminal of DUT
IH (current, high)
IH (Rd) or HD + to positive (+) terminal of DUT
PL (potential, low
PL (Bk/Wh) or LS
84
- to negative (-) terminal of DUT
7600 Plus LCR Meter
IL (current, low)
151053 A4
IL (Bk) or LD
- to negative (-) terminal of DUT
The PH (HS) and IH (HD) cables connect to the fixed arm of the tweezers (+) and the PL
(LS) and IL (LD) cables connect to the movable arm of the tweezers (-). To ensure valid
measurements it is especially important to observe the correct polarity when DC bias is to
be used.
2.14.6 Low V, Axial/Radial Lead Component Test Fixture (7000-06)
The 7000-06 Test Fixture, along with the BNC to BNC cable provided, is a method of
convenient, reliable, guarded 4-terminal connection of radial and axial leaded sensors and
components to the 7600 Plus. The 7000-06 consists of the test fixture and two axial lead
adapters.
Rotated 90 degrees
as shown
Axial Lead Adapter
Figure 60 Low V, Axial and Radial Lead Component Test Fixture
For this accessory an additional accuracy must be added to the standard instrument
accuracy as defined by AutoAcc.
For 1 MHz Special Case Accuracy
Primary readings: ± 0.06%
Secondary readings: ± 600 ppm
Connection to 7600 Plus (using 7000-01 or 7000-02 BNC Cable Sets):
Connect to 7600 Plus
Cable Marking/Color
Connect to Test Fixture
PH (potential, high)
PH (Red/white)
PH
IH (current, high)
IH (Red)
IH
PL (potential, low
PL (Black/white)
PL
IL (current, low)
IL (Black)
IL
If the device under test (DUT) is a radial lead component it can be inserted directly into
the fixture slots. The slots accommodate wires with diameters from 0.25 mm to 1 mm
(AWG 30 to AWG 18 wire). If the DUT is an axial-lead component the two axial lead
adapters should be installed in the fixture (by pushing vertically downward) and the
component installed in them. These adapters accommodate wire with diameters up to 1.5
mm (AWG 15 wire). When removing, lift with a gentle tilt left or right, never forward
or back.
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2.14.7 Open/Short Zeroing:
Instrument zeroing should be performed once the test fixture is connected. For an open, a
lead should be inserted in the + slot and another lead in the - slot to ensure good contact
between the wiper blades, and for a short the + and - contacts should be shorted together
with bus wire, the larger the better, but in accordance with wire sizes discussed above. It
should be noted that if measurements are to be made on the very lowest range (20 m
full scale), readings could be in error, although small, by the resistance value of the short
itself. The approximate value of the shorting wire can be determined by zeroing the
instrument using the standard 4-terminal Kelvin clips and then measuring the resistance
of the shorting wire.
2.14.8 Low V, Chip Component Test Fixture (7000-07)
The 7000-07 Test Fixture, along with the BNC to BNC cable provided, is a method of
convenient, reliable, guarded 4-terminal connection of chip or surface mount sensors and
components.
Figure 61 Low V Chip Component Test Fixture
Maximum Frequency:
2 MHz
Typical Residual Parameters (after performing open/short at DUT terminals):
C: < 0.15 (1 + 0.002/f)pF
L: < 10 (1 + 0.002/f)nH
R: < 1 (1 + f 2)m
where f = measurement frequency in MHz
Connection to 7600 Plus (using 7000-01 or 7000-02 BNC Cable Sets):
Connect to 7600 Plus
Cable Marking/Color
Connect to Test Fixture
PH (potential, high)
PH (Red/white)
PH
IH (current, high)
IH (Red)
IH
PL (potential, low
PL (Black/white)
PL
IL (current, low)
IL (Black)
IL
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Open/Short Zeroing:
Instrument zeroing should be performed once the test fixture is connected. Refer to the
instrument zeroing instructions for further information. For an OPEN the DUT should be
removed but the fixture spacing should be the same as the device. This can be done by
tightening the screw that holds the contact, as shown below. For a SHORT the fixture
contacts should be shorted together with a shorting block equivalent to spacing of the
device under test.
Use of this fixture may result in an incremental error due to residuals at DUT
terminals.
Verify with a known standard and apply this offset to final
measurements.
Same as
DUT'S width
Tightening Screw
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2.14.9 Calibration Kit (7000-09)
The 7000-09 Calibration kit consists of four calibration resistors, an open-circuit module
and a short-circuit module. These standards are NIST traceable and used to re calibrate
the 7600 Plus Precision LCR Meter. The four calibration resistors have nominal values
of 24.9, 374 ; 5.97 and 95.3 k. R and Q values are given for all four resistors at 1
kHz, R and Q values are also given at 25 kHz for the 95.3 k resistor, 250 kHz for the
5.97 k resistor and both 500 kHz and 1 MHz for the other two resistors. Use the 1 MHz
for calibration of 7600 Plus. Refer to Calibration on page 96.
Figure 62 Calibration Kit
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2.14.10Connection to "Type 874" Connectors
There are times when it may be desirable to connect the 7600 Plus to type 874 coaxial
connectors that are found on some impedance standards. This connection can be made
using either the 1689-9602 or 1689-9602-02 BNC to BNC Cable, two BNC Tees and two
BNC to 874 adapters (see below).
BNC Tee
To 874 on Impedance Standard
Cables from
7400/7500
BNC to 874
Figure 63 Connection to 874 Connectors
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7600 Plus LCR Meter
3
151053 A4
Error Messages
"AC CURRENT ERROR, SET TO 250A" AC current level improperly set
"AC VOLTAGE ERROR, SET TO 1V"
AC voltage level improperly set
"BAD CALIBRATION CODE ENTERED" Calibration code incorrectly entered
"BAD CALIBRATION DATA"
Calibration incorrect, re calibrate
"BAD OPEN CALIBRATION DATA"
Repeat Open test
"BAD SETUP DATA READ FROM MEMORY" Setup data incorrect, reload
"BAD SHORT CALIBRATION DATA"
Repeat Short test
"BIN CHECKSUM ERROR, TOTALS SET TO 0" Bin count incorrect
"CRC ERROR ON USB"
Stored setup lost or corrupt (cyclic-redundancy-check)
"CURRENT MODE, BIAS SET TO OFF"
"DISK WRITE PROTECT ERROR" Flash drive is write protected
"ELAPSED TIME ERROR, SET TO 0"
Elapsed time is incorrect and has been set to
zero (battery for non-volatile memory may be defective)
"ERROR DURING CALIBRATION"
Calibration incorrect, re calibrate
"ERROR DURING OPEN CALIBRATION"
Repeat Open test
"ERROR DURING SHORT CALIBRATION"
Repeat Short test
"FAILURE # SEE DOCUMENTATION" Hardware or software failure, 1 – 99 (# list
not included in this manual)
"FILE ACCESS VIOLATION"
File selected from flash drive is Read Only
"FILE DOES NOT EXIST" File name incorrect
"FILE EXISTS"
File already exists under the chosen name
"FLASH DRIVE NOT READY"
Flash drive defective or not inserted
"GENERAL FAILURE, USB"
Flash drive defective or not inserted
"HANDLER PORT FAILURE"
I/O port malfunction during power up
"HARDWARE TIMER FAILURE, REBOOT"
up
Hardware malfunction during power
"HIGH LIMIT LESS THAN LOW LIMIT" Limits incorrectly set
"INTERNAL HARDWARE FAILURE, REBOOT" Hardware malfunction during power
up
"INVALID FREQUENCY SELECTED"
"INVALID RANGE SELECTED"
Select a valid frequency
Select another range
"LOW BATTERY VOLTAGE"
Memory backup battery indicates low voltage;
setups and instrument zero could be lost
"MAXIMUM # OF SETUPS REACHED" Maximum number of files have been stored
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"NO IEEE 488 INTERFACE"
Unit does not include IEEE-488
"NO INTERLOCK SIGNAL"
Open interlock connection at rear panel I/O Port
"NO PASSWORD ENTERED"
Password entry canceled, re-enter
"NO ZERO DATA FOUND" Unit requires zeroing
"PASSWORD DID NOT MATCH" Incorrect password entered
"PASSWORD NOT SAVED IN RAM"
Error trying to save password, repeat
"PASSWORD VERIFICATION FAILURE" Wrong password entry for verification
"PRI & SEC MISMATCH, SET TO AUTO"
Check parameter selection
"PRIMARY = AUTO, CAN'T UPDATE AUTOACC"
Check parameter selection
"PRIMARY = AUTO, SECONDARY IGNORED" Check parameter selection
"PRINTER ERROR, CHECK PRINTER"
"PRINTER OUT OF PAPER"
Printer error
Printer out of paper
"QUICK OPEN / SHORT INVALID, RE-ZERO"
"REMOTE COMMAND INVALID" IEEE or RS232 command is incorrect (for example:
to set frequency use FREQuency)
"REMOTE COMMAND PARAMETER INVALID"
IEEE or RS232 parameter is
incorrect (for example: frequency parameter can be
XXXXXXX.XX)
"REMOTE COMMAND PREFIX INVALID"
IEEE or RS232 command prefix is
incorrect (for example: to configure unit use CONFigure)
"SHUT THE POWER OFF" Malfunction of instrument power source
"SWEEP BEGIN & END ARE EQUAL"
Sweep range improperly set
"SWEEP BEGIN / END VALUES TOO CLOSE" Sweep range improperly set
"SWEEP BEGIN VALUE GREATER THAN END"
"TIME / DATE ERROR, PLEASE SET"
Sweep range improperly set
Reset time and date
"TOO MANY KEYS, LAST KEY IGNORED"
Too many keys for entry field
“UNABLE TO READ FROM FLASH DRIVE"
Flash drive defective or not inserted
"UNABLE TO READ THAT FILENAME" Selected file unreadable, improper format
"UNABLE TO WRITE TO REMOTE"
not present
IEEE or RS232 not setup correctly or IEEE
"UNKNOWN COMMAND"
"UNKNOWN UNIT" Flash drive is not recognized (not present or defective)
"USB MEDIA DEFECT"
Flash drive defective
"USB READ FAULT"
Flash drive defective or not inserted
"USB SAVE ERROR"
Setup not properly saved
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"USB SECTOR UNFORMATTED" Flash drive is not formatted
"USB SEEK ERROR"
Flash drive defective or not inserted
"USB WRITE FAULT" Flash drive defective or not inserted
"VALID RANGE = low value - hi value"
values
Entry invalid, should be between specified
"WARNING V > 1, BIAS NOT AT 2V"
DC bias voltage incorrect
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7600 Plus LCR Meter
4
151053 A4
Theory
The 7600 Plus Precision LCR Meter consists of a standard mechanical package, LCD
display/keypad, PC104 microprocessor module, and power supply. In addition there is
the IEEE-488 card discussed briefly below.
4.1
Basic Instrument Architecture
4.1.1 Processor Board
The processor board provides the basic control for the 7600 Plus and mimics the IBM-PC
architecture. Besides the central processing unit and memory modules, it includes SMX
RTOS, keypad, USB and RS232 ports. The RS232 port is connected to its rear panel
connector by a cable. The processor board is stacked on the Main Board. The processor
board can have the IEEE-488 card stacked on it.
4.1.2 Power Supply
The power supply assembly consists of two modules, a +3V/+5V/-12V module towards
the back of the instrument and a ±12V module towards the front. The +3V/+5V/-12V
supplies power to all digital functions. The ±12V module supplies power to the analog
section of the instrument board.
4.1.3 LCD Display/Keypad Panel
The front panel user interface is comprised of a molded silicon rubber keypad that
actuates a membrane switch assembly. The keypad is environmentally sealed, designed
for long life with all keys providing tactile feedback to the operator. The 2 1/2" x 4 3/4"
LCD is a high resolution graphic display with on/off back light for visual clarity. Both
keypad and display are connected to the instrument I/O board via ribbon cables.
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7600 Plus LCR Meter
4.2
151053 A4
7600 Plus Instrument Module
The QT 1 Instrument Board QT0807 instrument board, used in the Model 7600 Plus
Precision LCR Meter, is the heart of the measurement system. There are five major parts
to this board: sine wave generator, voltage detector channel, current detector channel,
A/D converter, and Digital Signal Processor. Each is discussed below in brief.
4.2.1 Sine Wave Generator
All devices under test are tested by applying a sine wave of voltage or current. The sine
wave is generated by an IC using the Direct Digital Synthesis technique. This allows
generation of all frequencies from 10 Hz to 2 MHz with a high level of resolution.
4.2.2 Voltage Detector Channel
The sine wave test signal is applied to the unknown through the IH and IL leads, causing
a voltage to appear across the unknown. This voltage, Ex, is measured by the PH and PL
leads, filtered and amplified according to its level, and presented to one channel of the
Dual A/D converter.
4.2.3 Current Detector Channel
The current flowing through the unknown is applied to a transadmittance amplifier with
an internal standard in the feedback path. This arrangement causes a voltage to be
generated across the standard resistor proportional to the current. This voltage is also
filtered and amplified and presented to the second channel of the A/D converter.
4.2.4 A/D Converter
The two signals representing ‘voltage across’ and ‘current through’ the unknown are
digitized by a dual 18-bit A/D converter. Samples are taken synchronously with the
digital generation of the sine wave to obtain phase information.
4.2.5 Digital Signal Processor
The digitized voltage and current signals are applied to a high speed Digital Signal
Processor where a mathematical algorithm (similar to a Fast Fourier Transform) extracts
the in-phase and quadrature portions of the signal. This information is then used to
calculate the complex impedance, Z, and the complex admittance, Y, of the unknown.
These results are then used to compute the parameters requested by the user i.e. C, R, L,
D, Q etc.
4.3
Options
4.3.1 IEEE-488 Board & Cable (Discontinued)
Control available through the keyboard or available for display can be accessed over this
interface. This board is mounted at the right rear of the unit stacked above the processor
board. Connection to the IEEE-488 connector is via an interconnecting cable. IEEE
option is 7000-22.
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5
151053 A4
Maintenance & Calibration
Our warranty (at the front of this manual) attests to the quality of materials and
workmanship in our products. If malfunction should be suspected or other information
be desired, applications engineers are available for technical assistance. Application
assistance is available in the U.S. by calling 800-253-1230 and asking for Applications
Support. For support outside of the United States, please contact your local IET Labs
Distributor.
5.1
Bias Voltage Fuse Replacement
!
There are two bias voltage fuses. The fuses are type F0.25A, 250V, 5x20mm fast
blow. Replace only with the same rated fuse. Make sure the instrument is off and
disconnected from its ac power source. The fuses are located in the instrument on the
back panel QT110407 board.
5.2
Resetting of Time and Date
If for some reason the Time and Date need to be reset.
It is very important that the time and date be reset and the instrument zeroed
before proceeding with any measurements. Proceed as follows:
1. Press MENU key to select menu display.
2. Press Right or Left Arrow key to select Utilities menu.
3. Press Up or Down Arrow key to select Set Time/Date.
4. Press ENTER key to activate the entry field.
5. Set the current time and date as instructed on the display, refer to paragraph 2.6.5.7 if
necessary. After the time and date have been reset press MENU to return to the menu
display.
6. Press Up or Down Arrow key to select Zero.
7. Press ENTER key to activate the Zero routine and follow instructions on the
instrument display.
8. Once the Time and Date have been reset and the instrument zeroed the 7600 Plus is
ready for routine measurements. It's important to note that the elapsed time will have
been reset back to zero during this process.
5.3
Loss of Display Contrast
If for some reason the instrument should loose its display contrast, it is possible to reset it
easily using the procedure below. Loss of contrast would exhibit no display at all when
the instrument is powered up.
Procedure for restoring loss of contrast:
1. Consider the SELECT buttons as labeled 1, 2, 3, and 4 from top to bottom.
2. Turn the instrument on and wait 10 seconds.
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3. Press MENU key twice.
4. Press SELECT "4" one time.
5. Press SELECT "1" three times.
6. Press ENTER.
7. Press SELECT "1" many times till contrast returns to normal.
8. Press ENTER.
9. Arrow up to SAVE SETUP and save as DEFAULT.
If the above procedure fails to restore the contrast, try repeating. Failing restoration of
the contrast may be indication of another instrument problem.
5.4
Calibration
Calibration of the 7600 Plus Precision LCR Meter is recommended on an annual basis. If
the unit is to be returned to IET Labs for factory calibration, refer to section 5.4.2 for
instructions. Using the procedure below, the instrument can also be calibrated by a
qualified service person if traceable calibration equipment and standards are
available.
CAUTION
To ensure maximum stability, the instrument should be
powered up for a minimum of 1 hour before
calibration.
5.4.1
Requirements for Re calibration
Temperature stabilized room at 23 degrees C (73.4 F)
IET Labs 7000-09 Calibration Kit
1. Select CALIBRATION on the Utilities menu.
2. Once ENTER is selected the calibration code of 7600225 must be entered to
continue. This code is to prevent unauthorized personnel from effecting the
instrument calibration. For security reasons it may be desirable to blank out the
code (above) in this instruction manual.
The step by step instructions for this procedure is shown on the instrument display.
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5.4.2 Instrument Return
Before returning an instrument to IET Labs for Service please obtain an online Return
Materials Authorization Number (RMA#). This number, when placed on the outside of
the shipping package, will speed processing at our Service Lab and will serve as a
reference number for the time your unit is at IET Labs. Please contact our Sales
Department at 516-334-5959 for additional support.
It will be necessary to include a Purchase Order Number and credit card information to
insure expedient processing, although units found to be in warranty will be repaired at
no-charge. For any questions on repair costs or shipment instructions please contact our
CCC Department at the above number. To safeguard an instrument during storage and
shipping please use packaging that is adequate to protect it from damage, i.e., equivalent
to the original packaging and mark the box "Delicate Electronic Instrument”. Please
follow online instructions for shipping materials back to IET Labs.
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